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M. Costa

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DOI: 10.1007/jhep01(2010)109
2010
Cited 526 times
Combined measurement and QCD analysis of the inclusive e ± p scattering cross sections at HERA
A combination is presented of the inclusive deep inelastic cross sections measured by the H1 and ZEUS Collaborations in neutral and charged current unpolarised ep scattering at HERA during the period 1994-2000. The data span six orders of magnitude in negative four-momentum-transfer squared, Q^2, and in Bjorken x. The combination method used takes the correlations of systematic uncertainties into account, resulting in an improved accuracy. The combined data are the sole input in a NLO QCD analysis which determines a new set of parton distributions, HERAPDF1.0, with small experimental uncertainties. This set includes an estimate of the model and parametrisation uncertainties of the fit result.
DOI: 10.1016/s0168-9002(01)00560-5
2001
Cited 395 times
Radiation hard silicon detectors—developments by the RD48 (ROSE) collaboration
The RD48 (ROSE) collaboration has succeeded to develop radiation hard silicon detectors, capable to withstand the harsh hadron fluences in the tracking areas of LHC experiments. In order to reach this objective, a defect engineering technique was employed resulting in the development of Oxygen enriched FZ silicon (DOFZ), ensuring the necessary O-enrichment of about 2×1017 O/cm3 in the normal detector processing. Systematic investigations have been carried out on various standard and oxygenated silicon diodes with neutron, proton and pion irradiation up to a fluence of 5×1014 cm−2 (1 MeV neutron equivalent). Major focus is on the changes of the effective doping concentration (depletion voltage). Other aspects (reverse current, charge collection) are covered too and the appreciable benefits obtained with DOFZ silicon in radiation tolerance for charged hadrons are outlined. The results are reliably described by the “Hamburg model”: its application to LHC experimental conditions is shown, demonstrating the superiority of the defect engineered silicon. Microscopic aspects of damage effects are also discussed, including differences due to charged and neutral hadron irradiation.
DOI: 10.1140/epjc/s10052-023-11889-x
2023
Cited 23 times
Towards a Muon Collider
DOI: 10.1140/epjc/s10052-023-11889-x
2023
Cited 23 times
Towards a muon collider
DOI: 10.1140/epjc/s10052-023-11889-x
2023
Cited 23 times
Towards a Muon Collider
DOI: 10.1140/epjc/s10052-013-2311-3
2013
Cited 156 times
Combination and QCD analysis of charm production cross section measurements in deep-inelastic ep scattering at HERA
Measurements of open charm production cross sections in deep-inelastic ep scattering at HERA from the H1 and ZEUS Collaborations are combined. Reduced cross sections $\sigma_{\rm red}^{c\bar{c}}$ for charm production are obtained in the kinematic range of photon virtuality 2.5≤Q 2≤2000 GeV2 and Bjorken scaling variable 3⋅10−5≤x≤5⋅10−2. The combination method accounts for the correlations of the systematic uncertainties among the different data sets. The combined charm data together with the combined inclusive deep-inelastic scattering cross sections from HERA are used as input for a detailed NLO QCD analysis to study the influence of different heavy flavour schemes on the parton distribution functions. The optimal values of the charm mass as a parameter in these different schemes are obtained. The implications on the NLO predictions for W ± and Z production cross sections at the LHC are investigated. Using the fixed flavour number scheme, the running mass of the charm quark is determined.
DOI: 10.1161/circinterventions.115.003551
2016
Cited 79 times
Neurological Events Following Transcatheter Aortic Valve Replacement and Their Predictors
Background— The risk for stroke after transcatheter aortic valve replacement (TAVR) is an important concern. Identification of predictors for stroke is likely to be a critical factor aiding patient selection and management as TAVR use becomes widespread. Methods and Results— Patients enrolled in the CoreValve US Extreme Risk and High Risk Pivotal Trials or Continued Access Study treated with the self-expanding CoreValve bioprosthesis were included in this analysis. The 1-year stroke rate after TAVR was 8.4%. Analysis of the stroke hazard rate identified an early phase (0–10 days; 4.1% of strokes) and a late phase (11–365 days; 4.3% of strokes). Baseline predictors of early stroke included National Institutes of Health stroke scale score >0, prior stroke, prior transient ischemic attack, peripheral vascular disease, absence of prior coronary artery bypass surgery, angina, low body mass index (<21 kg/m 2 ), and falls within the past 6 months. Significant procedural predictors were total time in the catheterization laboratory or operating room, delivery catheter in the body time, rapid pacing used during valvuloplasty, and repositioning of the prosthesis. Predictors of stroke between 11 and 365 days were small body surface area, severe aortic calcification, and falls within the past 6 months. There were no significant imaging predictors of early or late stroke. Conclusions— Predictors of early stroke after TAVR included clinical and procedural factors; predictors of later stroke were limited to patient but not anatomic characteristics. These findings indicate that further refinement of imaging to identify anatomic factors predisposing to embolization may help improve stroke prediction in patients undergoing TAVR. Clinical Trial Registrations— URL: http://www.clinicaltrials.gov . Unique identifiers: NCT01240902, NCT01531374.
DOI: 10.1016/j.nima.2021.165319
2021
Cited 37 times
Resistive AC-Coupled Silicon Detectors: Principles of operation and first results from a combined analysis of beam test and laser data
This paper presents the principles of operation of Resistive AC-Coupled Silicon Detectors (RSDs) and measurements of the temporal and spatial resolutions using a combined analysis of laser and beam test data. RSDs are a new type of n-in-p silicon sensor based on the Low-Gain Avalanche Diode (LGAD) technology, where the n+ implant has been designed to be resistive, and the read-out is obtained via AC-coupling. The truly innovative feature of RSD is that the signal generated by an impinging particle is shared isotropically among multiple read-out pads without the need for floating electrodes or an external magnetic field. Careful tuning of the coupling oxide thickness and the n+ doping profile is at the basis of the successful functioning of this device. Several RSD matrices with different pad width-pitch geometries have been extensively tested with a laser setup in the Laboratory for Innovative Silicon Sensors in Torino, while a smaller set of devices have been tested at the Fermilab Test Beam Facility with a 120 GeV/c proton beam. The measured spatial resolution ranges between 2.5μm for 70–100 pad-pitch geometry and 17μm with 200–500 matrices, a factor of 10 better than what is achievable in binary read-out (binsize∕12). Beam test data show a temporal resolution of ∼40ps for 200 μm pitch devices, in line with the best performances of LGAD sensors at the same gain.
DOI: 10.1016/j.snb.2023.133559
2023
Cited 8 times
Disposable electrochemical sensor based on ion imprinted polymeric receptor for Cd(II) ion monitoring in waters
Cadmium is a highly toxic heavy metal, even at low concentrations. Moreover, it bio-accumulates with a long biological half-life producing a wide variety of acute and chronic effects like cancer in humans. Therefore, there is significant interest in providing a portable and user-friendly sensor for heavy metal detection. A highly sensitive and selective electrochemical sensor for Cd(II) determination was developed as an alternative. The Cd (II) receptors were integrated into the sensor using an ion-imprinted polymer film (IIPs film). Accordingly, 4-aminophenylacetic acid (4-APA) was electropolymerised in the presence of Cd(II) ions as a template using cyclic voltammetry (CV) on screen-printed carbon electrodes (SPCEs). Imprinted cavities were obtained after the alkaline elution of ions. Sensor characterisation was performed using SEM, ATR-FTIR and electrochemical methods, such as cyclic voltammetry (CV) and electrochemical Impedance Spectroscopy (EIS), and compared to control experiments (not imprinted polymeric film, NIP film). Analytical performances of the IIP sensor revealed a sensitivity 5-order of magnitude higher than the NIP response in a concentration range from 10 to 1200 nM of Cd (II). This technology can potentially be applied for water quality control and monitoring of heavy metals.
DOI: 10.1016/j.nima.2007.04.157
2007
Cited 82 times
The silicon microstrip sensors of the ATLAS semiconductor tracker
This paper describes the AC-coupled, single-sided, p-in-n silicon microstrip sensors used in the Semiconductor Tracker (SCT) of the ATLAS experiment at the CERN Large Hadron Collider (LHC). The sensor requirements, specifications and designs are discussed, together with the qualification and quality assurance procedures adopted for their production. The measured sensor performance is presented, both initially and after irradiation to the fluence anticipated after 10 years of LHC operation. The sensors are now successfully assembled within the detecting modules of the SCT, and the SCT tracker is completed and integrated within the ATLAS Inner Detector. Hamamatsu Photonics Ltd. supplied 92.2% of the 15,392 installed sensors, with the remainder supplied by CiS.
DOI: 10.1016/j.jcin.2011.04.007
2011
Cited 58 times
Impact of Drug Release Kinetics on Vascular Response to Different Zotarolimus-Eluting Stents Implanted in Patients With Long Coronary Stenoses
We assessed the in vivo vascular response to a new generation of zotarolimus-eluting stents (ZES) with prolonged drug release (Resolute ZES-SR, Medtronic Vascular, Santa Rosa, California) compared with ZES with faster kinetics (Endeavor ZES-FR, Medtronic Vascular) by optical coherence tomography.Local drug release kinetics has been implicated with antirestenosis efficacy of drug-eluting stents. However, the impact of different release kinetics on vascular response of diseased human coronary arteries remains to be investigated.The study population consisted of 43 patients with long lesions in native coronary vessels treated with multiple overlapping ZES. Twenty-one patients treated with ZES-SR were compared with 22 patients treated with ZES-FR from the ODESSA (Optical coherence tomography for DES SAfety) study. The primary endpoint was in-stent neointimal hyperplasia as assessed by optical coherence tomography at 6-month follow-up. Coprimary endpoints were the percentage of uncovered and malapposed struts.Strut-level median neointimal thickness was 0.11 mm (interquartile range [IQR]: 0.07 to 0.15 mm) in ZES-SR and 0.31 mm (IQR: 0.27 to 0.42 mm) in ZES-FR, respectively (p < 0.001). The 6-month rate of uncovered struts per patient was 7.38% (IQR: 3.06% to 12.72%) in ZES-SR and 0.00% (IQR: 0.00% to 0.00%) in ZES-FR (p < 0.001); rate of malapposed and uncovered struts was 1.47% (IQR: 0.32% to 4.23%) in ZES-SR and 0.00% (IQR: 0.00% to 0.00%) in ZES-FR (p < 0.001).This study demonstrated the impact of different release kinetics on human in vivo vascular response to ZES implantation. The new generation of ZES-SR compared with ZES-FR had better suppression of the neointimal response but higher proportion of uncovered and malapposed struts at 6-month optical coherence tomography follow-up. (Optical Coherence Tomography in Long Lesions [LongOCT]; NCT01133925).
DOI: 10.1109/tsp.2014.2336636
2014
Cited 55 times
A Steered-Response Power Algorithm Employing Hierarchical Search for Acoustic Source Localization Using Microphone Arrays
The localization of a speaker inside a closed environment is often approached by real-time processing of multiple audio signals captured by a set of microphones. One of the leading related methods for sound source localization, the steered-response power (SRP), searches for the point of maximum power over a spatial grid. High-accuracy localization calls for a dense grid and/or many microphones, which tends to impractically increase computational requirements. This paper proposes a new method for sound source localization (called H-SRP), which applies the SRP approach to space regions instead of grid points. This arrangement makes room for the use of a hierarchical search inspired by the branch-and-bound paradigm, which is guaranteed to find the global maximum in anechoic environments and shown experimentally to also work under reverberant conditions. Besides benefiting from the improved robustness of volume-wise search over point-wise search as to reverberation effects, the H-SRP attains high performance with manageable complexity. In particular, an experiment using a 16-microphone array in a typical presentation room yielded localization errors of the order of 7 cm, and for a given fixed complexity, competing methods' errors are two to three times larger.
DOI: 10.1016/j.physletb.2012.01.025
2012
Cited 48 times
Search for single-top production in ep collisions at HERA
A search for single-top production, ep→etX, has been performed with the ZEUS detector at HERA using data corresponding to an integrated luminosity of 0.37 fb−1. No evidence for top production was found, consistent with the expectation from the Standard Model. Limits were computed for single-top production via flavour changing neutral current transitions involving a neutral electroweak vector boson, γ or Z. The result was combined with a previous ZEUS result yielding a total luminosity of 0.50 fb−1. A 95% credibility level upper limit of 0.13 pb was obtained for the cross section at the centre-of-mass energy of s=315 GeV.
DOI: 10.1016/j.nuclphysb.2012.06.006
2012
Cited 43 times
Inclusive-jet photoproduction at HERA and determination of
Inclusive-jet cross sections have been measured in the reaction ep→e+jet+X for photon virtuality Q2<1 GeV2 and γp centre-of-mass energies in the region 142<Wγp<293 GeV with the ZEUS detector at HERA using an integrated luminosity of 300 pb−1. Jets were identified using the kT, anti-kT or SIScone jet algorithms in the laboratory frame. Single-differential cross sections are presented as functions of the jet transverse energy, ETjet, and pseudorapidity, ηjet, for jets with ETjet>17 GeV and −1<ηjet<2.5. In addition, measurements of double-differential inclusive-jet cross sections are presented as functions of ETjet in different regions of ηjet. Next-to-leading-order QCD calculations give a good description of the measurements, except for jets with low ETjet and high ηjet. The influence of non-perturbative effects not related to hadronisation was studied. Measurements of the ratios of cross sections using different jet algorithms are also presented; the measured ratios are well described by calculations including up to O(αs2) terms. Values of αs(MZ) were extracted from the measurements and the energy-scale dependence of the coupling was determined. The value of αs(MZ) extracted from the measurements based on the kT jet algorithm is αs(MZ)=0.1206−0.0022+0.0023(exp.)−0.0035+0.0042(th.); the results from the anti-kT and SIScone algorithms are compatible with this value and have a similar precision.
DOI: 10.1140/epjc/s10052-011-1557-x
2011
Cited 39 times
A study of the b-quark fragmentation function with the DELPHI detector at LEP I and an averaged distribution obtained at the Z Pole
The nature of b-quark jet hadronisation has been investigated using data taken at the Z peak by the DELPHI detector at LEP. Two complementary methods are used to reconstruct the energy of weakly decaying b-hadrons, $E_{\mathrm{B}}^{\mathrm{weak}}$ . The average value of $x^{\mathrm{weak}}_{\mathrm{B}} = E_{\mathrm{B}}^{\mathrm{weak}}/E_{\mathrm{beam}}$ is measured to be 0.699±0.011. The resulting $x^{\mathrm{weak}}_{\mathrm{B}}$ distribution is then analysed in the framework of two choices for the perturbative contribution (parton shower and Next to Leading Log QCD calculation) in order to extract measurements of the non-perturbative contribution to be used in studies of b-hadron production in other experimental environments than LEP. In the parton shower framework, data favour the Lund model ansatz and corresponding values of its parameters have been determined within PYTHIA 6.156 from DELPHI data: $$a= 1.84^{+0.23}_{-0.21}\quad\mbox{and}\quad b=0.642^{+0.073}_{-0.063}~\mathrm{GeV}^{-2},$$ with a correlation factor ρ=92.2%. Combining the data on the b-quark fragmentation distributions with those obtained at the Z peak by ALEPH, OPAL and SLD, the average value of $x^{\mathrm{weak}}_{\mathrm{B}}$ is found to be 0.7092±0.0025 and the non-perturbative fragmentation component is extracted. Using the combined distribution, a better determination of the Lund parameters is also obtained: $$a= 1.48^{+0.11}_{-0.10}\quad\mbox{and}\quad b=0.509^{+0.024}_{-0.023}~\mathrm{GeV}^{-2},$$ with a correlation factor ρ=92.6%.
DOI: 10.1140/epjc/s10052-012-2175-y
2012
Cited 36 times
Combined inclusive diffractive cross sections measured with forward proton spectrometers in deep inelastic ep scattering at HERA
A combination of the inclusive diffractive cross section measurements made by the H1 and ZEUS Collaborations at HERA is presented. The analysis uses samples of diffractive deep inelastic ep scattering data at a centre-of-mass energy sqrt(s) = 318 GeV where leading protons are detected by dedicated spectrometers. Correlations of systematic uncertainties are taken into account, resulting in an improved precision of the cross section measurement which reaches 6% for the most precise points. The combined data cover the range 2.5 < Q2 < 200 GeV2 in photon virtuality, 0.00035 < xIP < 0.09 in proton fractional momentum loss, 0.09 < |t| < 0.55 GeV2 in squared four-momentum transfer at the proton vertex and 0.0018 < beta < 0.816 in beta = x/xIP, where x is the Bjorken scaling variable.
DOI: 10.1016/j.nima.2020.164383
2020
Cited 21 times
LGAD designs for Future Particle Trackers
Several future high-energy physics facilities are currently being planned. The proposed projects include high energy e+e− circular and linear colliders, hadron colliders, and muon colliders, while the Electron–Ion Collider (EIC) is expected to construct at the Brookhaven National Laboratory in the future. Each proposal has its advantages and disadvantages in terms of readiness, cost, schedule, and physics reach, and each proposal requires the design and production of specific new detectors. This paper first presents the performances necessary for future silicon tracking systems at the various new facilities. Then it illustrates a few possibilities for the realization of such silicon trackers. The challenges posed by the future facilities require a new family of silicon detectors, where features such as impact ionization, radiation damage saturation, charge sharing, and analog read-out are exploited to meet these new demands.
DOI: 10.1140/epjc/s10052-008-0528-3
2008
Cited 39 times
Study of W-boson polarisations and triple gauge boson couplings in the reaction e+e-→W+W- at LEP 2
A determination of the single W spin density matrix (SDM) elements in the reaction e+e-→W+W-→lνqq̄(l=e/μ) is reported at centre-of-mass energies between 189 and 209 GeV. The data sample used corresponds to an integrated luminosity of 520 pb-1 taken by DELPHI between 1998 and 2000. The single W SDM elements, ρττ' W± (τ,τ'=± 1 or 0), are determined as a function of the W- production angle with respect to the e- beam direction and are obtained from measurements of the W decay products by the application of suitable projection operators, Λττ', which assume the V-A coupling of the W-boson to fermions. The measured SDM elements are used to obtain the fraction of longitudinally polarised Ws, with the result: $\frac{\sigma_{\text{L}}}{\sigma_{{\text{tot}}}} = 24.9 \pm4.5({\text{stat}}) \pm2.2({\text{syst}})\%$ at a mean energy of 198 GeV. The SDM elements are also used to determine the triple gauge couplings Δg1 Z,Δκγ,λγ and g4 Z, $\tilde{\kappa}_{Z}$ and $\tilde{\lambda}_{Z}$ . For the CP-violating couplings the results of single parameter fits are: $g_4^{{Z}} = -0.39^{+0.19}_{-0.20}$ $\tilde{\kappa}_{{Z}} = -0.09^{+0.08}_{-0.05}$ $\tilde{\lambda}_{{Z}} = -0.08\pm0.07 .$ The errors are a combination of statistical and systematic errors. All results are consistent with the Standard Model.
DOI: 10.1140/epjc/s10052-010-1498-9
2010
Cited 33 times
Measurement of high-Q 2 charged current deep inelastic scattering cross sections with a longitudinally polarised positron beam at HERA
Measurements of the cross sections for charged current deep inelastic scattering in e + p collisions with a longitudinally polarised positron beam are presented. The measurements are based on a data sample with an integrated luminosity of 132 pb−1 collected with the ZEUS detector at HERA at a centre-of-mass energy of 318 GeV. The total cross section is presented at positive and negative values of the longitudinal polarisation of the positron beams. The single-differential cross-sections dσ/dQ 2, dσ/dx and dσ/dy are presented for Q 2>200 GeV2. The reduced cross-section $\tilde{\sigma}$ is presented in the kinematic range 200<Q 2<60 000 GeV2 and 0.006<x<0.562. The measurements agree well with the predictions of the Standard Model. The results are used to determine a lower limit on the mass of a hypothetical right-handed W boson.
DOI: 10.1007/jhep09(2013)058
2013
Cited 29 times
Measurement of charm fragmentation fractions in photoproduction at HERA
A bstract The production of D 0 , D * + , D + , $ D_s^{+} $ and $ \Lambda_c^{+} $ charm hadrons and their antiparticles in ep scattering at HERA has been studied with the ZEUS detector, using a total integrated luminosity of 372 pb −1 . The fractions of charm quarks hadronising into a particular charm hadron were derived. In addition, the ratio of neutral to charged D -meson production rates, the fraction of charged D mesons produced in a vector state, and the stangeness-suppression factor have been determined. The measurements have been performed in the photoproduction regime. The charm hadrons were reconstructed in the range of transverse momentum p T &gt; 3 . 8 GeV and pseudorapidity | η | &lt; 1 . 6. The charm fragmentation fractions are compared to previous results from HERA and from e + e − experiments. The data support the hypothesis that fragmentation is independent of the production process.
DOI: 10.1088/1748-0221/16/03/p03019
2021
Cited 14 times
First application of machine learning algorithms to the position reconstruction in Resistive Silicon Detectors
Abstract RSDs (Resistive AC-Coupled Silicon Detectors) are n-in-p silicon sensors based on the LGAD (Low-Gain Avalanche Diode) technology, featuring a continuous gain layer over the whole sensor area. The truly innovative feature of these sensors is that the signal induced by an ionising particle is seen on several pixels, allowing the use of reconstruction techniques that combine the information from many read-out channels. In this contribution, the first application of a machine learning technique to RSD devices is presented. The spatial resolution of this technique is compared to that obtained with the standard RSD reconstruction methods that use analytical descriptions of the signal sharing mechanism. A Multi-Output regressor algorithm, trained with a combination of simulated and real data, leads to a spatial resolution of less than 2 μm for a sensor with a 100 μm pixel. The prospects of future improvements are also discussed.
DOI: 10.1016/j.nima.2022.167228
2022
Cited 9 times
4D tracking: present status and perspectives
The past ten years have seen the advent of silicon-based precise timing detectors for charged particle tracking. The underlying reason for this evolution is a design innovation: the Low-Gain Avalanche Diode (LGAD). In its simplicity, the LGAD design is an obvious step with momentous consequences: low gain leads to large signals maintaining sensors stability and low noise, allowing sensor segmentation. Albeit introduced for a different reason, to compensate for charge trapping in irradiated silicon sensors, LGAD found fertile ground in the design of silicon-based timing detectors. Spurred by this design innovation, solid-state-based timing detectors for charged particles are going through an intense phase of R&D, and hybrid and monolithic sensors, with or without internal gain, are being explored. This contribution offers a review of this booming field.
DOI: 10.1016/j.physletb.2010.06.015
2010
Cited 29 times
Inclusive-jet cross sections in NC DIS at HERA and a comparison of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"><mml:msub><mml:mi>k</mml:mi><mml:mi>T</mml:mi></mml:msub></mml:math>, anti-<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.gif" overflow="scroll"><mml:msub><mml:mi>k</mml:mi><mml:mi>T</mml:mi></mml:msub></mml:math> and SIScone jet algorithms
For the first time, differential inclusive-jet cross sections have been measured in neutral current deep inelastic ep scattering using the anti-kT and SIScone algorithms. The measurements were made for boson virtualities Q2>125 GeV2 with the ZEUS detector at HERA using an integrated luminosity of 82 pb−1 and the jets were identified in the Breit frame. The performance and suitability of the jet algorithms for their use in hadron-like reactions were investigated by comparing the measurements to those performed with the kT algorithm. Next-to-leading-order QCD calculations give a good description of the measurements. Measurements of the ratios of cross sections using different jet algorithms are also presented; the measured ratios are well described by calculations including up to O(αs3) terms. Values of αs(MZ) were extracted from the data; the results are compatible with and have similar precision to the value extracted from the kT analysis.
DOI: 10.1103/physrevd.86.012005
2012
Cited 25 times
Search for first-generation leptoquarks at HERA
A search for first-generation leptoquarks was performed in electron-proton and positron-proton collisions recorded with the ZEUS detector at HERA in 2003-2007 using an integrated luminosity of 366 pb^-1. Final states with an electron and jets or with missing transverse momentum and jets were analysed, searching for resonances or other deviations from the Standard Model predictions. No evidence for any leptoquark signal was found. The data were combined with data previously taken at HERA, resulting in a total integrated luminosity of 498 pb^-1. Limits on the Yukawa coupling, lambda, of leptoquarks were set as a function of the leptoquark mass for different leptoquark types within the Buchmueller-Rueckl-Wyler model. Leptoquarks with a coupling lambda=0.3 are excluded for masses up to 699 GeV.
DOI: 10.1016/j.nima.2020.164375
2020
Cited 17 times
State-of-the-art and evolution of UFSD sensors design at FBK
In the past few years, there has been growing interest in the development of silicon sensors able to simultaneously measure accurately the time of passage and the position of impinging charged particles. In this contribution, a review of the progresses in the design of UFSD (Ultra-Fast Silicon Detectors) sensors, manufactured at the FBK (Fondazione Bruno Kessler) Foundry, aiming at tracking charged particles in 4 dimensions, is presented. The state-of-the-art UFSD sensors, with excellent timing capability, are planned to be used in both ATLAS and CMS experiments detector upgrade, in order to reduce the background due to the presence of overlapping events in the same bunch crossing. The latest results on sensors characterization including time resolution, radiation resistance and uniformity of the response are here summarized, pointing out the interplay between the design of the gain layer and the UFSD performances. The research is now focusing on the maximization of the sensor fill factor, to be able to reduce the pixel size, exploring the implementation of shallow trenches for the pixel isolation and the development of resistive AC-coupled UFSD sensors. In conclusion, a brief review on research paths tailored for detection of low energy X-rays or for low material budget applications is given.
DOI: 10.1016/j.nima.2022.166739
2022
Cited 8 times
Optimization of the gain layer design of ultra-fast silicon detectors
In the past few years, the need of measuring accurately the spatial and temporal coordinates of the particles generated in high-energy physics experiments has spurred a strong R&D in the field of silicon sensors. Within these research activities, the so-called Ultra-Fast Silicon Detectors (UFSDs), silicon sensors optimized for timing based on the Low-Gain Avalanche Diode (LGAD) design, have been proposed and adopted by the CMS and ATLAS collaborations for their respective timing layers. The defining feature of the Ultra-Fast Silicon Detectors (UFSDs) is the internal multiplication mechanism, determined by the gain layer design. In this paper, the performances of several types of gain layers, measured with a telescope instrumented with a 90Sr β-source, are reported and compared. The measured sensors are produced by Fondazione Bruno Kessler (FBK) and Hamamatsu Photonics (HPK). The sensor yielding the best performance, both when new and irradiated, is an FBK 45 μm-thick sensor with a carbonated deep gain implant, where the carbon and the boron implants are annealed concurrently with a low thermal load. This sensor is able to achieve a time resolution of 40 ps up to a radiation fluence of 2.5⋅1015 neq/cm2, delivering at least 5 fC of charge.
DOI: 10.1016/j.nima.2022.167374
2022
Cited 7 times
DC-coupled resistive silicon detectors for 4D tracking
In this work, we introduce a new design concept: the DC-coupled Resistive Silicon Detectors, based on the LGAD technology.This new design intends to address a few known drawbacks of the first generation of AC-coupled Resistive Silicon Detectors (RSD).The sensor behaviour is simulated using a fast hybrid approach based on a combination of two packages, Weightfield2 and LTSpice.The simulation demonstrates that the key features of the RSD design are maintained, yielding excellent space and time resolutions: a few tens of ps and a few microns.In this report, we will outline the optimization methodology and the results of the simulation.We will also present detailed studies on the effects induced by the choice of key design parameters on the space and time resolutions provided by this sensor.
DOI: 10.1016/j.nima.2023.168671
2023
High-precision 4D tracking with large pixels using thin resistive silicon detectors
The basic principle of operation of silicon sensors with resistive read-out is built-in charge sharing. Resistive Silicon Detectors (RSD, also known as AC-LGAD), exploiting the signals seen on the electrodes surrounding the impact point, achieve excellent space and time resolutions even with very large pixels. In this paper, a TCT system using a 1064 nm picosecond laser is used to characterize RSD sensors produced by Fondazione Bruno Kessler. The paper first introduces the parametrization of the errors in the determination of the position and time coordinates in RSD, then outlines the reconstruction method, and finally presents the results. Three different pixel pitches are used in the analysis: 200 × 340, 450 × 450, and 1300 × 1300 μm2. At gain = 30, the 450 × 450 μm2 pixel achieves a time jitter of 20 ps and a spatial resolution of 15 μm concurrently, while the 1300 × 1300 μm2 pixel achieves 30 ps and 30 μm, respectively. The implementation of cross-shaped electrodes improves considerably the response uniformity over the pixel surface.
DOI: 10.1088/1748-0221/19/01/c01028
2024
Machine learning for precise hit position reconstruction in Resistive Silicon Detectors
Abstract RSDs are LGAD silicon sensors with 100% fill factor, based on the principle of AC-coupled resistive read-out. Signal sharing and internal charge multiplication are the RSD key features to achieve picosecond-level time resolution and micron-level spatial resolution, thus making these sensors promising candidates as 4D-trackers for future experiments. This paper describes the use of a neural network to reconstruct the hit position of ionizing particles, an approach that can boost the performance of the RSD with respect to analytical models. The neural network has been trained in the laboratory and then validated on test beam data. The device-under-test in this work is a 450 μm-pitch matrix from the FBK RSD2 production, which achieved a resolution of about 65 μm at the DESY Test Beam Facility, a 50% improvement compared to a simple analytical reconstruction method, and a factor two better than the resolution of a standard pixel sensor of equal pitch size with binary read-out. The test beam result is compatible with the laboratory ones obtained during the neural network training, confirming the ability of the machine learning model to provide accurate predictions even in environments very different from the training one. Prospects for future improvements are also discussed.
DOI: 10.36557/2674-8169.2024v6n1p1440-1456
2024
COMPLICAÇÕES NO LEVANTAMENTO DO SEIO MAXILAR
Existem muitas técnicas e materiais cirúrgicos diferentes para o levantamento do seio maxilar bem como diferentes técnicas podem ser usadas para aumentar nos seios da face, muitas variáveis podem alterar o resultado da cirurgia. Algumas delas são únicas ou de longo prazo. Para pacientes com problemas graves de reabsorção óssea e dentária, o alongamento do assoalho do seio maxilar e o enxerto ósseo podem ser opções confiáveis. A elevação do seio maxilar é descrita como uma cirurgia eletiva de leve a moderada, sendo a colocação imediata do implante, o método de restauração mais comumente realizado. Embora a elevação do seio maxilar não seja um procedimento muito complicado e seja um procedimento comumente realizado em implantodontia, é importante prestar o máximo de atenção possível aos aspectos anatômicos para evitar complicações durante ou após a cirurgia.
DOI: 10.48550/arxiv.2402.01517
2024
Achieving a combined 15 microns and 60 ps test beam resolution using an RSD 450 microns pitch pixel matrix connected to a FAST2 ASIC
This paper reports on the spatial and temporal resolutions of an RSD 450 microns pitch pixels array measured at the DESY test beam facility. RSDs, Resistive Silicon Detectors, also known as AC-LGAD, achieve excellent position and temporal resolution by exploiting charge sharing among neighboring electrodes. The RSD matrix used in this study is part of the second FBK RSD production, RSD2, composed of 450-micron pitch pixels with cross-shaped electrodes. A 7-pixel matrix was read out by the FAST2 ASIC, a 16-channel amplifier fully custom ASIC developed by INFN Torino using the 110 nm CMOS technology. The total area covered by the matrix is about 1.5 mm2. The position resolution reached in this test is 15 microns, about 3.4% of the pitch. The temporal resolution achieved in this work is 60 ps, dominated by the FAST2 resolution. The work also demonstrates that RSD sensors achieve 100% fill factor and homogenous resolutions over the whole matrix surface, making them suitable for 4D tracking applications.
DOI: 10.1016/j.nima.2024.169153
2024
Design optimization of the UFSD inter-pad region
This paper reports on a measurement campaign to characterize the inter-pad region of Ultra-Fast Silicon Detectors (UFSDs) manufactured by Fondazione Bruno Kessler. The devices under test are either pixel or strip arrays, featuring a large number of different inter-pad layouts; both pre-irradiation and irradiated sensors have been measured. The aim of the study is to link the design parameters of the inter-pad region to the operation of the sensors, providing insights into the design of UFSD arrays with narrow inter-pad gaps. We concluded that, in the UFSD design, the doping level and the area of the p-stop should be kept low, in order to avoid the early breakdown of the device and the micro-discharges effect; UFSDs with such characteristics proved also rather insensitive to floating pads and irradiation. Thanks to these findings, it was possible to design a UFSD array that yields the expected performance with an inter-pad width as small as 25 μm, significantly improving its fill factor with respect to standard designs. Two innovative experimental techniques are presented in this work: the first one is based on a TCT setup, the second makes use of an ultra-low light CCD camera.
DOI: 10.29327/5365942
2024
DESAFIOS DA EDUCAÇÃO PARA O FUTURO - Volume 1
A escola de hoje não pode se limitar a reproduzir por si só as informações contidas no livro didático. Ela deve estabelecer um elo entre a cultura que acontece fora do contexto escolar (na rua, nas praças, na família, na internet) e a cultura formal. Pois, assim sendo os alunos vão aprendendo a buscar a informação através dos meios de comunicação, fazendo uma ligação com as informações obtidas na sala de aula, analisando criticamente, dando-lhes significado pessoal e social, juntamente com o professor, que tem o papel insubstituível de mediador, auxiliando o aluno para fazer a síntese entre a cultura formal e a cultura popular. Portanto uma educação capaz de articular antigos e novos saberes, compreendendo seus contextos, sendo mediadora entre ambos, sob a perspectiva da complexidade, interdisciplinaridade e que encontrem ressonâncias em paradigmas que pleiteiem a educação emocional do ser em sua integralidade, ofertando novos caminhos, através de ferramentas utilizadas em prol de uma gestão da emoção voltada para a aprendizagem. Assim a educação está em constate transformação devendo estar permanentemente atenta as novas tendências para o fazer e refazer pedagógico, acreditamos que essas pesquisas podem ser utilizadas como arcabouço e contribuir para o processo de ensino e aprendizagem.
DOI: 10.36926/editorainovar-978-65-5388-203-4_011
2024
IMPACTO DA PANDEMIA DE COVID-19 NA EDUCAÇÃO INFANTIL: A UTILIZAÇÃO DA ARTE COM ESTRATÉGIA DE APRENDIZAGEM NAS PRÁTICAS PEDAGÓGICAS
Nos últimos anos a sociedade vem passando por diversas transformações as quais reverberam na educação e no processo ensino-aprendizagem do aluno. A cada momento, a partir da necessidade que vai surgindo na sala de aula, o professor precisa se renovar, ampliar seus conhecimentos, repensar suas práticas e adaptá-las as necessidades do aluno e do contexto no qual se insere. Por outro lado, destacam-se experiências as quais nos motivam e nos faz refletir o real papel e significado da educação na sociedade. Este livro busca a partir de seus textos, refletir sobre a educação, focando nas práticas do professor em sala de aula, suas vivências e os dilemas que os mesmos enfrentam em seu cotidiano. Os capítulos propostos para a obra transitam por uma gama de temas, os quais refletem questões desde a inclusão e o lúdico, ao uso de novas metodologia em sala de aula perpassam pela gestão escolar e pelas práticas dos professores. Tudo isso nos faz pensar a dinâmica educacional, além de trazer ao debate outras temáticas relacionadas a educação. Assim, acreditamos que por mais que as reflexões pontuem um tema voltado para a questão educacional, fazendo os recortes metodológicos necessários, percebemos que estes nunca esgotarão o mesmo, pois falar de educação, das práticas, vivências e dilemas é falar de uma dinâmica convidativa, que está em constante transformação. ISBN 978-65-5388-203-4DOI 10.36926/editorainovar-978-65-5388-203-4 Biografia do Organizador Sílvio César Lopes da Silva - Possui graduação em Letras - Língua Portuguesa pela Universidade Estadual da Paraíba, graduação em Filosofia pelo Centro Universitário Assunção e graduação em Pedagogia pela Universidade Cruzeiro do Sul; Doutorado em Educação - UFRN; Mestrado Profissional em Formação de Professores pela Universidade Estadual da Paraíba - UEPB; Especialista em Educação e em Linguística Aplicada. Tem experiência na área de Educação, com ênfase em tecnologias, estudos etnográficos e redes sociais. Atua nas Linhas de pesquisa: Estudos etnográficos e formação docente (OPEM - Observatório de Pesquisas e Estudos Multidisciplinares - Pesquisador); e Processos Socioculturais e de Significação (GEMINI - Grupo de Estudos de Mídia - Análises e Pesquisas em Cultura, Processos e Produtos Midiáticos - estudante).
DOI: 10.5935/978-85-514-1214-5.c0001
2024
ATUALIZAÇÃO EM LITÍASE URINÁRIA
DOI: 10.1136/ejhpharm-2024-eahp.274
2024
4CPS-170 Clinical pharmacy prioritisation algorithm for patients in psychiatric long-term care: a pilot study
DOI: 10.61164/rjnm.v2i1.2146
2024
A INFLUÊNCIA DA MÍDIA NO TRIBUNAL DO JÚRI
O estudo tem como objetivo analisar os efeitos produzidos pela influência da mídia brasileira nos votos dos jurados em casos de grande repercussão nacional. Trata-se de pesquisa qualitativa, realizada por meio de método dialético, sendo que foram utilizadas revisões bibliográficas para a definição e análise através de contraposição de posicionamento dos doutrinadores sobre o tema, além de pesquisas jornalísticas dos casos que tiverem notória influência da mídia. A princípio, demonstra-se a importância do Tribunal do Júri, apresentando as noções gerais sobre esse procedimento, a competência para julgamento dos crimes dolosos contra a vida, os princípios norteadores do Tribunal do Júri, dando ênfase aos princípios da plenitude da defesa, do sigilo das votações e da soberania dos vereditos. Após, analise-se a mídia e sua função de informação, contrapondo com a formação de opinião da sociedade brasileira. Por conseguinte, conclui-se com a apresentação de casos de grande repercussão nacional que tiveram forte influência midiática no julgamento realizado perante a alçada do Tribunal do Júri.
DOI: 10.1088/1748-0221/19/04/c04022
2024
Characterization of thin carbonated LGADs after irradiation up to 2.5· 10<sup>15</sup> n<sub>1 Mev eq.</sub>/cm<sup>2</sup>
Abstract EXFLU1 is a new batch of radiation-resistant silicon sensors manufactured at Fondazione Bruno Kessler (FBK, Italy). The EXFLU1 sensors utilize thin substrates that remain operable even after extensive irradiation. They incorporate Low-Gain Avalanche Diode (LGAD) technology, enabling internal multiplication of charge carriers to boost the small signal produced by a particle crossing their thin active thicknesses, ranging from 15 to 45 μ m. To address current challenges related to acceptor removal, the EXFLU1 production incorporates improved defect engineering techniques. This includes the so called carbonated LGADs, where carbon doping is implanted alongside boron in the gain layer. This contribution focuses on evaluating the performances of thin sensors with carbonated gain layer from the EXFLU1 production, before and after irradiation up to 2.5· 10 15 n 1 Mev eq. /cm 2 . The conducted tests involve static and transient characterizations, including I-V and C-V measurements, as well as laser and β -source tests. This work aims to present the state of the art in LGAD sensor technology with a carbonated gain layer and shows the characterization of the most radiation-resistant LGAD sensors produced to date.
DOI: 10.29327/5394226
2024
PRÁTICAS E PESQUISAS EM EDUCAÇÃO
A obra contribui para o desenvolvimento dos profissionais da educação, todo sistema educacional brasileiro, proporcionando aos leitores aprendizagens e reflexões acerca da realidade da educação brasileira, a fim de compreender os desafios que vivenciam os educadores em nosso país, bem como contribuir para o seu desenvolvimento. O foco das práticas pedagógicas conduzidas pelos autores está baseada nos preceitos da interatividade, na partilha de saberes, nas trocas de experiências e no respeito às diferenças.
DOI: 10.36926/editorainovar-978-65-5388-222-5_019
2024
USO DAS TICS NA EDUCAÇÃO ESPECIAL: REFLEXÃO SOBRE SEUS ESTIGMAS, DESAFIOS E AVANÇOS
Este livro apresenta uma coletânea de artigos científicos que investigam as práticas de inclusão e da diversidade em contextos multidisciplinares. Os autores, provenientes de diferentes áreas do saber, convergem no tratamento de temas pertinentes à inclusão social, cultural e educacional, apresentando pesquisas e análises críticas baseadas em dados empíricos e fundamentação teórica. Os trabalhos aqui reunidos abordam estratégias de inclusão e destacam a importância de ambientes acessíveis e respeitosos para todos. As contribuições são unificadas pelo objetivo comum de fornecer insights práticos e teóricos que possam ser implementados para promover uma sociedade mais inclusiva. Estudos sobre a diversidade, incluindo questões de gênero, raça, habilidade e muito mais, e como essas dimensões intersectam com as políticas e práticas atuais, estão nas páginas deste livro. "Inclusão e Diversidade em Ação: Uma Visão Multidisciplinar" oferece um panorama relevante para todos que estão empenhados na promoção de uma inclusão efetiva e no reconhecimento da diversidade como um valor intrínseco ao progresso humano. ISBN: 978-65-5388-222-5DOI: 10.36926/editorainovar-978-65-5388-222-5 Biografia da Organizadora Liliane Pereira de Souza - Doutora em Educação pela Universidade Estadual Júlio de Mesquita Filho; (UNESP). Foi aluna especial do doutorado da Faculdade de Educação da Universidade Estadual de Campinas (UNICAMP, 2015). Mestra em Educação pela Universidade Federal de Mato Grosso do Sul. Possui graduação em Administração, Pedagogia e Sociologia. É avaliadora externa convidada da Comissão de Seleção e de Julgamento de Projetos de Extensão e Pesquisa da Universidade Estadual do Rio Grande do Sul (UERGS, CNPq e FAEPRGS) desde 2016. É revisora do periódico Revista Docência do Ensino Superior da Universidade Federal de Minas Gerais. É professora universitária em cursos de graduação e pós-graduação. É pesquisadora desde 2005.
DOI: 10.1140/epjp/s13360-024-05130-1
2024
Characterisation of the neutron sources in use at STUK SSDL through a new transfer instrument with spectrometric capabilities
Abstract Characterising neutron sources for calibration or generic testing purposes is a complex task, as the neutron spectrum may depend, to some extent, on the construction characteristics of the source. Bonner spheres (BS) are the traditional spectrometric transfer instruments, but they are very sensitive to room scatter and required measurements are highly time consuming. The recently developed NCT-WES device, belonging to the family of the Single Moderator Neutron Spectrometers, has been proposed as a convenient alternative to BS. This work presents the results of a demonstration campaign organised at the STUK neutron metrology laboratory (Finland) in July 2023, where the spectra from two 252 Cf and two 241 Am-Be sources were determined. For the 241 Am-Be sources, the results were compared to the spectra of two categories recently introduced by ISO 8529-1. Based on the results it was concluded that the “large” source category is an appropriate selection for STUK sources. The campaign also proved the operational advantages of NCT-WES as spectrometric transfer instrument.
DOI: 10.51161/conbrasau2024/31198
2024
AVALIAÇÃO DE POLÍTICAS PÚBLICAS PARA A PRIMEIRA INFÂNCIA: PROJETO PIPAS NO CEARÁ
DOI: 10.1140/epjc/s10052-010-1504-2
2010
Cited 20 times
Inclusive dijet cross sections in neutral current deep inelastic scattering at HERA
Single- and double-differential inclusive dijet cross sections in neutral current deep inelastic ep scattering have been measured with the ZEUS detector using an integrated luminosity of 374 pb^-1. The measurement was performed at large values of the photon virtuality, Q^2, between 125 and 20000 GeV^2. The jets were reconstructed with the k_T cluster algorithm in the Breit reference frame and selected by requiring their transverse energies in the Breit frame, E_T,B^jet, to be larger than 8 GeV. In addition, the invariant mass of the dijet system, M_jj, was required to be greater than 20 GeV. The cross sections are described by the predictions of next-to-leading-order QCD.
DOI: 10.1140/epjc/s10052-010-1423-2
2010
Cited 19 times
Measurement of beauty production in DIS and extraction at ZEUS
Beauty production in deep inelastic scattering with events in which a muon and a jet are observed in the final state has been measured with the ZEUS detector at HERA using an integrated luminosity of 114 pb^-1. The fraction of events with beauty quarks in the data was determined using the distribution of the transverse momentum of the muon relative to the jet. The cross section for beauty production was measured in the kinematic range of photon virtuality, Q^2 &gt; 2 Gev^2, and inelasticity, 0.05 &lt; y &lt; 0.7, with the requirement of a muon and a jet. Total and differential cross sections are presented and compared to QCD predictions. The beauty contribution to the structure function F_2 was extracted and is compared to theoretical predictions.
DOI: 10.1016/j.physletb.2012.01.009
2012
Cited 18 times
Measurement of the t dependence in exclusive photoproduction of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"><mml:mi>ϒ</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:mn>1</mml:mn><mml:mi>S</mml:mi><mml:mo stretchy="false">)</mml:mo></mml:math> mesons at HERA
The exclusive photoproduction reaction gamma p -> Upsilon(1S) p has been studied with the ZEUS detector in ep collisions at HERA using an integrated luminosity of 468 pb^-1. The measurement covers the kinematic range 60<W<220 GeV and Q^2<1 GeV^2, where W is the photon-proton centre-of-mass energy and Q^2 is the photon virtuality. The exponential slope, b, of the t dependence of the cross section, where t is the squared four-momentum transfer at the proton vertex, has been measured, yielding b = 4.3 +2.0 -1.3 (stat.) +0.5 -0.6 (syst.) GeV^-2. This constitutes the first measurement of the t dependence of the gamma p -> Upsilon(1S) p cross section.
DOI: 10.1103/physrevd.87.052014
2013
Cited 18 times
Measurement of high-<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mi>Q</mml:mi><mml:mn>2</mml:mn></mml:msup></mml:math>neutral current deep inelastic<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mi>e</mml:mi><mml:mo mathvariant="bold">+</mml:mo></mml:msup><mml:mi>p</mml:mi></mml:math>scattering cross sections with a longitudinally polarized positron beam at HERA
Measurements of neutral current cross sections for deep inelastic scattering in ${e}^{+}p$ collisions at HERA with a longitudinally polarized positron beam are presented. The single-differential cross-sections $d\ensuremath{\sigma}/d{Q}^{2}$, $d\ensuremath{\sigma}/dx$ and $d\ensuremath{\sigma}/dy$ and the reduced cross section $\stackrel{\texttildelow{}}{\ensuremath{\sigma}}$ are measured in the kinematic region ${Q}^{2}&gt;185\text{ }\text{ }{\mathrm{GeV}}^{2}$ and $y&lt;0.9$, where ${Q}^{2}$ is the four-momentum transfer squared, $x$ the Bjorken scaling variable and $y$ the inelasticity of the interaction. The measurements are performed separately for positively and negatively polarized positron beams. The measurements are based on an integrated luminosity of $135.5\text{ }\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$ collected with the ZEUS detector in 2006 and 2007 at a center-of-mass energy of 318 GeV. The structure functions ${\stackrel{\texttildelow{}}{F}}_{3}$ and ${F}_{3}^{\ensuremath{\gamma}Z}$ are determined by combining the ${e}^{+}p$ results presented in this paper with previously published ${e}^{\ensuremath{-}}p$ neutral current results. The asymmetry parameter ${A}^{+}$ is used to demonstrate the parity violation predicted in electroweak interactions. The measurements are well described by the predictions of the Standard Model.
DOI: 10.1007/jhep05(2013)097
2013
Cited 15 times
Measurement of D*± production in deep inelastic scattering at HERA
A bstract The production of D *± mesons in deep inelastic ep scattering has been measured for exchanged photon virtualities 5 &lt; Q 2 &lt; 1000 GeV 2 , using an integrated luminosity of 363 pb −1 with the ZEUS detector at HERA. Differential cross sections have been measured and compared to next-to-leading-order QCD calculations. The cross-sections are used to extract the charm contribution to the proton structure functions, expressed in terms of the reduced charm cross section, $ \sigma_{\mathrm{red}}^{{c\overline{c}}} $ . Theoretical calculations based on fits to inclusive HERA data are compared to the results.
DOI: 10.1016/j.nuclphysb.2012.09.007
2013
Cited 14 times
Production of the excited charm mesons and at HERA
The production of the excited charm mesons D1(2420) and D2⁎(2460) in ep collisions has been measured with the ZEUS detector at HERA using an integrated luminosity of 373pb−1. The masses of the neutral and charged states, the widths of the neutral states, and the helicity parameter of D1(2420)0 were determined and compared with other measurements and with theoretical expectations. The measured helicity parameter of the D10 allows for some mixing of S- and D-waves in its decay to D⁎±π∓. The result is also consistent with a pure D-wave decay. Ratios of branching fractions of the two decay modes of the D2⁎(2460)0 and D2⁎(2460)± states were measured and compared with previous measurements. The fractions of charm quarks hadronising into D1 and D2⁎ were measured and are consistent with those obtained in e+e− annihilations.
DOI: 10.1140/epjc/s10052-007-0304-9
2007
Cited 18 times
Investigation of Colour Reconnection in WW events with the DELPHI detector at LEP-2
In the reaction e+e-→WW→(q1q̄2)(q3q̄4) the usual hadronization models treat the colour singlets q1q̄2 and q3q̄4 coming from two W bosons independently. However, since the final state partons may coexist in space and time, cross-talk between the two evolving hadronic systems may be possible during fragmentation through soft gluon exchange. This effect is known as colour reconnection. In this article the results of the investigation of colour reconnection effects in fully hadronic decays of W pairs in DELPHI at LEP are presented. Two complementary analyses were performed, studying the particle flow between jets and W mass estimators, with negligible correlation between them, and the results were combined and compared to models. In the framework of the SK-I model, the value for its κ parameter most compatible with the data was found to be: κSK-I=2.2+2.5 -1.3 corresponding to the probability of reconnection $\mathcal{P}_{\text{reco}}$ to be in the range $0.31 <\mathcal{P}_{{\text{reco}}} < 0.68$ at 68% confidence level with its best value at 0.52.
DOI: 10.1140/epjc/s10052-008-0779-z
2008
Cited 17 times
Observation of the muon inner bremsstrahlung at LEP1
Muon bremsstrahlung photons converted in front of the DELPHI main tracker (TPC) in dimuon events at LEP1 were studied in two photon kinematic ranges: 0.2<E γ ≤1 GeV and transverse momentum with respect to the parent muon p T <40 MeV/c, and 1<E γ ≤10 GeV and p T <80 MeV/c. A good agreement of the observed photon rate with predictions from QED for the muon inner bremsstrahlung was found, contrary to the anomalous soft photon excess that has been observed recently in hadronic Z 0 decays. The obtained ratios of the observed signal to the predicted level of the muon bremsstrahlung are 1.06±0.12±0.07 in the photon energy range 0.2<E γ ≤1 GeV and 1.04±0.09±0.12 in the photon energy range 1<E γ ≤10 GeV. The bremsstrahlung dead cone is observed for the first time in the direct photon production at LEP.
DOI: 10.1140/epjc/s10052-011-1573-x
2011
Cited 14 times
Measurement of beauty production in deep inelastic scattering at HERA using decays into electrons
The production of beauty quarks in ep interactions has been studied with the ZEUS detector at HERA for exchanged four-momentum squared Q^2 > 10 GeV^2, using an integrated luminosity of 363 pb^{-1}. The beauty events were identified using electrons from semileptonic b decays with a transverse momentum 0.9 < p_T^e < 8 GeV and pseudorapidity |eta^e| < 1.5. Cross sections for beauty production were measured and compared with next-to-leading-order QCD calculations. The beauty contribution to the proton structure function F_2 was extracted from the double-differential cross section as a function of Bjorken-x and Q^2.
DOI: 10.1140/epjc/s10052-011-1659-5
2011
Cited 13 times
Measurement of heavy-quark jet photoproduction at HERA
Photoproduction of beauty and charm quarks in events with at least two jets has been measured with the ZEUS detector at HERA using an integrated luminosity of 133 pb−1. The fractions of jets containing b and c quarks were extracted using the invariant mass of charged tracks associated with secondary vertices and the decay-length significance of these vertices. Differential cross sections as a function of jet transverse momentum, $p_{\mathrm {T}}^{\mathrm{jet}}$ , and pseudorapidity, η jet, were measured. The data are compared with previous measurements and are well described by next-to-leading-order QCD predictions.
DOI: 10.1007/jhep05(2013)023
2013
Cited 12 times
Measurement of D ± production in deep inelastic ep scattering with the ZEUS detector at HERA
A bstract Charm production in deep inelastic ep scattering was measured with the ZEUS detector using an integrated luminosity of 354 pb −1 . Charm quarks were identified by reconstructing D ± mesons in the D ± → K ∓ π ± π ± decay channel. Lifetime information was used to reduce combinatorial background substantially. Differential cross sections were measured in the kinematic region 5 &lt; Q 2 &lt; 1000 GeV 2 , 0 . 02 &lt; y &lt; 0 . 7, 1 . 5 &lt; p T ( D ± ) &lt; 15 GeV and | η ( D ± )| &lt; 1 . 6, where Q 2 is the photon virtuality, y is the inelasticity, and p T ( D ± ) and η ( D ± ) are the transverse momentum and the pseudorapidity of the D ± meson, respectively. Next-to-leading-order QCD predictions are compared to the data. The charm contribution, $ F_2^{{c\overline{c}}} $ , to the proton structure-function F 2 was extracted.
DOI: 10.1016/j.apradiso.2015.07.039
2015
Cited 12 times
Design and simulation of an optimized e-linac based neutron source for BNCT research
The paper is focused on the study of a novel photo-neutron source for BNCT preclinical research based on medical electron Linacs. Previous studies by the authors already demonstrated the possibility to obtain a mixed thermal and epithermal neutron flux of the order of 10(7) cm(-2) s(-1). This paper investigates possible Linac's modifications and a new photo-converter design to rise the neutron flux above 5 10(7) cm(-2) s(-1), also reducing the gamma contamination.
DOI: 10.1016/j.nima.2018.04.040
2018
Cited 11 times
A Bonner Sphere Spectrometer based on a large 6LiI(Eu) scintillator: Calibration in reference monoenergetic fields
A Bonner Sphere spectrometer employing a large, 11 mm diameter × 3 mm thickness, 6LiI(Eu) scintillator (LL-BSS), was assembled. The purpose was to produce a BSS similar in sensitivity to those based on 3He sensors, but using alternative sensors. With respect to the traditional BSS based on the 4 mm (diameter) × 4 mm (height) 6LiI(Eu), this new BSS is a factor of 3 more sensitive. LL-BSS response matrix, determined with MCNPX, was experimentally evaluated with monoenergetic reference neutron fields of 144 keV, 565 keV and 1.2 MeV available at NPL (Teddington, UK). The results of the experiment confirmed the correctness of the response matrix within an overall uncertainty lower than ±2%.
DOI: 10.1016/j.physletb.2012.07.031
2012
Cited 10 times
Measurement of isolated photons accompanied by jets in deep inelastic ep scattering
The production of isolated high-energy photons accompanied by jets has been measured in deep inelastic ep scattering with the ZEUS detector at HERA, using an integrated luminosity of 326pb−1. Measurements were made for exchanged photon virtualities, Q2, in the range 10 to 350GeV2. The photons were measured in the transverse-energy and pseudorapidity ranges 4<ETγ<15GeV and −0.7<ηγ<0.9, and the jets were measured in the transverse-energy and pseudorapidity ranges 2.5<ETjet<35GeV and −1.5<ηjet<1.8. Differential cross sections are presented as functions of these quantities. Perturbative QCD predictions give a reasonable description of the shape of the measured cross sections over most of the kinematic range, but the absolute normalisation is typically in disagreement by 20–30%.
DOI: 10.1016/j.nima.2019.02.031
2019
Cited 10 times
CYSP-BEAM: A multi-detector directional spectrometer for in-beam neutron spectrometry
CYSP-BEAM is a directional neutron spectrometer formed by a thick polyethylene cylindrical collimator followed by a sensitive capsule that contains several active thermal neutron detectors located at different depths along the cylindrical axis. Due to a thick lateral shield made of polyethylene and borated rubber, only neutrons from the direction identified by the collimating aperture can reach the internal detectors. As the response function of the internal detectors tend to peak at increasing energies as the detector depth increases, the device has spectrometric properties. This type of moderated spectrometer, whose prototype was the CYSP (CYlindrical SPectrometer), is capable to combine the functionalities of Bonner Spheres in a single device, thus requiring only one exposure to measure all the energy components of the incident beam, from thermal up to GeV neutrons. The neutron spectrum is obtained via few-channel unfolding methods. With respect to the original CYSP, the new CYSP-BEAM device is optimized to operate in the direct intense beam of neutron producing installations, such as large scale neutron science facilities. Compared with CYSP, CYSP-BEAM has narrower collimating aperture and the internal detectors have sensibility a factor 100 lower. Its response matrix was simulated using MCNPX. This paper describes the new device focusing on the internal detectors, the response matrix and the test measurement performed using the 14 MeV beam produced at the ENEA Frascati Neutron Generator (FNG).
DOI: 10.1016/j.nima.2019.02.070
2019
Cited 9 times
Neutron spectrometry of a lightly encapsulated 241Americium–beryllium neutron source using two different Bonner Sphere Spectrometers
241Americium–beryllium neutron sources are used in a variety of applications, spanning from the civil engineering to the oil industry, and to the radiation dosimetry. The ISO 8529-1 Standard reports a reference distribution for the energy of the emitted neutrons, which extends from 0.1 to 11 MeV. Nevertheless every source exhibits a slightly different spectrum, depending on the material and dimension of the capsule, and on the amount of active material. This source-to-source variability is expected to mainly affect the energy region below 0.1 MeV. As these differences can be important in the fields of neutron dosimetry and metrology, some relevant source formats have been investigated with spectrometric methods. The neutron calibration laboratory of the Politecnico di Milano recently acquired a CZ/1003/S — 96 type 241 Am–Be source (nominal emission rate 2.2E+6 s−1). As this type of source is in use in a number of European laboratories, its spectrum was determined through a neutron spectrometry experiment, involving two Bonner sphere spectrometers with well-known responses. The experimental spectrum is compared to that published for a similar source and to the ISO-recommended one.
DOI: 10.48550/arxiv.2203.07261
2022
Cited 4 times
The physics case of a 3 TeV muon collider stage
In the path towards a muon collider with center of mass energy of 10 TeV or more, a stage at 3 TeV emerges as an appealing option. Reviewing the physics potential of such muon collider is the main purpose of this document. In order to outline the progression of the physics performances across the stages, a few sensitivity projections for higher energy are also presented. There are many opportunities for probing new physics at a 3 TeV muon collider. Some of them are in common with the extensively documented physics case of the CLIC 3 TeV energy stage, and include measuring the Higgs trilinear coupling and testing the possible composite nature of the Higgs boson and of the top quark at the 20 TeV scale. Other opportunities are unique of a 3 TeV muon collider, and stem from the fact that muons are collided rather than electrons. This is exemplified by studying the potential to explore the microscopic origin of the current $g$-2 and $B$-physics anomalies, which are both related with muons.
DOI: 10.3389/fpsyg.2022.857419
2022
Cited 4 times
Appraisal Bias and Emotion Dispositions Are Risk Factors for Depression and Generalized Anxiety: Empirical Evidence
Appraisal theory of emotion predicts that appraisal biases may generate stable emotion dispositions, which can ultimately lead to affective disorders. One example is the habitual underestimation of one's potential to cope with adverse events, which favors frequent experiences of sadness and worry and therefore increases the risk for development of depression and generalized anxiety disorders. To examine the relationships between these variables as potential risk factors, in Study 1, we used appraisal and emotion questions in the Swiss Household Panel (SHP), a nationwide representative sample, and analyzed data for N = 4,859 participants in one annual survey wave (Wave 14, SHP 2012) via theory-based hierarchical regressions. Path analysis of the nomological network linking frequent experiences of depression and anxiety to the emotion dispositions of sadness and worry, and measures of perceived coping potential (appraisal bias) supports the theoretical predictions and further identifies the effects of important background variables such as personality, motivation, and life events. Discriminant analysis shows that these predictors allow correct classification of close to 70% of the participants with elevated risk. In Study 2, we used established validated instruments to assess the risk for depression and anxiety disorders, as well as a recently validated scenario method to assess appraisal bias and emotion disposition in a survey with N = 152 students. The results correspond to the theoretical predictions and largely confirm the findings with the household survey. The results of both studies demonstrate the utility of using current emotion theory to provide new vistas for research on risk factors for affective disorders and to inform the development of appropriate interventions to reduce the level of risk.
DOI: 10.48550/arxiv.2303.08533
2023
Towards a Muon Collider
A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by the recently-formed International Muon Collider Collaboration. This Review summarises the status and the recent advances on muon colliders design, physics and detector studies. The aim is to provide a global perspective of the field and to outline directions for future work.
DOI: 10.1140/epjc/s10052-009-0917-2
2009
Cited 12 times
A study of ${\mathrm{b}}\bar{\mathrm{b}}$ production in e+e− collisions at $\sqrt{s}=130$ –207 GeV
Measurements are presented of R b, the ratio of the ${\mathrm{b}}\bar{\mathrm{b}}$ cross-section to the ${\mathrm{q}}\bar{\mathrm{q}}$ cross-section in e+e− collisions, and the forward-backward asymmetry A FB b at twelve energy points in the range $\sqrt{s}=130$ –207 GeV. These results are found to be consistent with the Standard Model expectations. The measurements are used to set limits on new physics scenarios involving contact interactions.
DOI: 10.1109/tns.2007.894368
2007
Cited 11 times
Strategies and Tools for ATLAS Online Monitoring
ATLAS is one of the four experiments under construction along the Large Hadron Collider (LHC) ring at CERN. The LHC will produce interactions at a center-of-mass energy equal to radics = 14 TeV with a frequency of 40 MHz. The detector consists of more than 140 million electronic channels. The challenging experimental environment and the extreme detector complexity impose the necessity of a common, scalable, distributed monitoring framework, which can be tuned for optimal use by different ATLAS sub-detectors at the various levels of the ATLAS data flow. This paper presents the architecture of this monitoring software framework and describes its current implementation, which has already been used at the ATLAS beam test activity in 2004. Preliminary performance results, obtained on a computer cluster consisting of 700 nodes, will also be presented, showing that the performance of the current implementation is within the range of the final ATLAS requirements.
DOI: 10.1007/jhep03(2010)035
2010
Cited 9 times
Events with an isolated lepton and missing transverse momentum and measurement of W production at HERA
A search for events containing an isolated electron or muon and missing transverse momentum produced in e ± p collisions is performed with the H1 and ZEUS detectors at HERA. The data were taken in the period 1994–2007 and correspond to an integrated luminosity of 0.98 fb−1. The observed event yields are in good overall agreement with the Standard Model prediction, which is dominated by single W production. In the e + p data, at large hadronic transverse momentum P T X > 25GeV, a total of 23 events are observed compared to a prediction of 14.0 ± 1.9. The total single W boson production cross section is measured as 1.06 ± 0.16 (stat.) ± 0.07 (sys.) pb, in agreement with an Standard Model (SM) expectation of 1.26 ± 0.19 pb.
DOI: 10.1016/j.physletb.2012.11.051
2013
Cited 8 times
Production of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"><mml:msup><mml:mrow><mml:mi>Z</mml:mi></mml:mrow><mml:mrow><mml:mn>0</mml:mn></mml:mrow></mml:msup></mml:math> bosons in elastic and quasi-elastic ep collisions at HERA
The production of Z0 bosons in the reaction ep -> eZ0p*, where p* stands for a proton or a low-mass nucleon resonance, has been studied in ep collisions at HERA using the ZEUS detector. The analysis is based on a data sample collected between 1996 and 2007, amounting to 496 pb-1 of integrated luminosity. The Z0 was measured in the hadronic decay mode. The elasticity of the events was ensured by a cut on eta_max < 3.0, where eta_max is the maximum pseudorapidity of energy deposits in the calorimeter defined with respect to the proton beam direction. A signal was observed at the Z0 mass. The cross section of the reaction ep -> eZ0p* was measured to be sigma(ep -> eZ0p*) = 0.13 +/- 0.06 (stat.) +/- 0.01 (syst.) pb, in agreement with the Standard Model prediction of 0.16 pb. This is the first measurement of Z0 production in ep collisions.
DOI: 10.1016/s0168-9002(00)00180-7
2000
Cited 14 times
Recent results from the ATLAS SCT irradiation programme
The irradiation facility at the CERN proton synchrotron, set up to irradiate full-size prototypes of silicon microstrip detectors for the ATLAS semiconductor tracker, is described and measurements of the detector currents during irradiation are reported. The detector dark currents can be described by bulk radiation damage models demonstrating the radiation hardness of the detector design and allowing the current damage factor α and the acceptor introduction term β to be determined. Results from testbeam studies of a module with an irradiated detector and binary readout in a magnetic field and with the beam incident over a range of angles are reported. The hit efficiency and spatial resolution satisfy the requirements for the SCT provided the detector is operated at the full charge collection voltage. The Lorentz angle was not found to be affected by the irradiation.
DOI: 10.1016/j.physletb.2011.01.051
2011
Cited 7 times
Measurement of the energy dependence of the total photon–proton cross section at HERA
The energy dependence of the photon–proton total cross section, σtotγp, was determined from e+p scattering data collected with the ZEUS detector at HERA at three values of the center-of-mass energy, W, of the γp system in the range 194<W<296 GeV. This is the first determination of the W dependence of σtotγp from a single experiment at high W. Parameterizing σtotγp∝W2ϵ, ϵ=0.111±0.009(stat.)±0.036(syst.) was obtained.
DOI: 10.1209/0295-5075/127/12002
2019
Cited 6 times
Thermal to GeV neutron spectrometry of the INES beam line at ISIS using the CYSP-BEAM spectrometer
The neutron energy distribution of the INES beam line, extending from thermal up to nearly 800 MeV, was measured by means of the CYSP-BEAM broad energy range spectrometer. The latter is an innovative type of moderator-based directional neutron spectrometer, based on multiple thermal neutron detectors embedded in a collimated cylindrical structure. Its operation principle is the same as the Bonner sphere spectrometer (BSS), but only one exposure is needed to simultaneously determine all energy components. This paper describes the performance of the spectrometer, from the response of the internal thermal neutron detectors to the spectrum unfolding. This paper opens the way for a new generation of real-time spectrometric devices for quality assurance of neutron beamlines.
DOI: 10.1088/1748-0221/16/08/p08055
2021
Cited 5 times
Design of a novel compact neutron collimator
In this work the concept of a novel slow neutron collimator and the way to operate it are presented. The idea is based on the possibility to decouple the device's field-of-view from its collimation power. A multi-channel geometry is proposed consisting of a chess-board structure where highly neutron-absorbing channels are alternated to air channels. A borated polymer was purposely developed to produce the attenuating components in the form of square-sectioned long rods. A scalable structure consisting of multiple collimation sectors can be arranged. The geometrical parameter L/D, corresponding to the ratio between the length of a channel and its width, defines the collimation power. Several sectors can be arranged one after the other to reach relevant collimation powers. Each sector, 100 mm long, is composed by several channels with D = 2.5 mm corresponding to an L/D coefficient of 40. The target field of view is 50×50 mm2. This novel collimator, developed inside the INFN-ANET collaboration, due to its intrinsic compactness, will be of great importance to enhance the neutron imaging capability of small to medium-size neutron sources.
DOI: 10.1016/s0370-2693(01)01282-5
2002
Cited 12 times
Search for charged Higgs bosons in e+e− collisions at s=189–202 GeV
A search for pair-produced charged Higgs bosons was performed in the high energy data collected by the DELPHI detector at LEP II at centre-of-mass energies from 189 GeV to 202 GeV. The three different final states, \tau \nu \tau \nu, c \bar s \bar c s and c \bar s \tau \nu were considered. New methods were applied to reject wrong hadronic jet pairings and for the tau identification, where a discriminator based on tau polarisation and polar angles was used. No excess of data compared to the expected Standard Model processes was observed and the existence of a charged Higgs boson with mass lower than 71.5 GeV/c^2 is excluded at the 95% confidence level.
DOI: 10.1093/rpd/ncx298
2018
Cited 6 times
DEVELOPING RADIATION RESISTANT THERMAL NEUTRON DETECTORS FOR THE E_LIBANS PROJECT: PRELIMINARY RESULTS
Radiation-resistant, gamma-insensitive, active thermal neutron detectors were developed to monitor the thermal neutron cavity of the E_LIBANS project. Silicon and silicon carbide semiconductors, plus vented air ion chambers, were chosen for this purpose. This communication describes the performance of these detectors, owing on the results of dedicated measurement campaigns.
DOI: 10.1088/1748-0221/3/09/p09004
2008
Cited 6 times
Alignment of the Pixel and SCT Modules for the 2004 ATLAS Combined Test Beam
A small set of final prototypes of the ATLAS Inner Detector silicon tracking system (Pixel Detector and SemiConductor Tracker), were used to take data during the 2004 Combined Test Beam. Data were collected from runs with beams of different flavour (electrons, pions, muons and photons) with a momentum range of 2 to 180 GeV/c. Four independent methods were used to align the silicon modules. The corrections obtained were validated using the known momenta of the beam particles and were shown to yield consistent results among the different alignment approaches. From the residual distributions, it is concluded that the precision attained in the alignment of the silicon modules is of the order of 5 μm in their most precise coordinate.
DOI: 10.1016/j.apradiso.2018.09.018
2018
Cited 5 times
CYSP-HS: A new version of the CYSP directional neutron spectrometer with increased sensitivity
CSYP (CYlindrical SPectrometer) is a directional neutron spectrometer based on a single moderator embedding multiple thermal neutron detectors. Similarly to Bonner Spheres, CYSP responds from thermal up to GeV neutrons and the spectrum is obtained via few-channel unfolding methods. CYSP has the shape of a polyethylene cylinder with diameter 50 cm and height 65 cm. Owing on a thick collimator and on a specifically designed shielding structure, the internal detectors only respond to neutrons coming from a known direction. Internal thermal neutron detectors are one-cm2 6LiF-covered silicon diodes. Un upgraded version of CYPS was developed to work in low intensity applications, such as cosmic field measurements. It is called CYSP-HS (High-Sensitivity) and is equipped with large area 6LiF-covered silicon diodes (LATND, Large Area Thermal Neutron Detectors). Compared with the former CYSP, the sensitivity increased approximately by an order of magnitude. This paper presents CYSP-HS focusing on the new internal detectors, the response matrix and its verification in a reference field of Am-Be available at the Politecnico di Milano.
DOI: 10.1016/j.nima.2019.06.028
2019
Cited 5 times
An active Bonner sphere spectrometer for intense neutron fields
Neutron producing installations can be characterized by the presence of intense pulsed fields, possibly accompanied by large photon background. This is the case of particle accelerators and, more recently, laser-based radiation sources. Determining neutron spectra in these fields is particularly complex, as active detectors may likely be affected by dead-time and saturation effects, and their parasitic response to photons is generally non zero. Passive Bonner Spheres Spectrometers (BSS) equipped with activation foils have been used in these cases. Owing on a new type of active thermal neutron detector (TNRD, Thermal Neutron Rate Detector), this work presents a BSS able to operate in intense, pulsed fields, with large photon background. The response matrix of this spectrometer was experimentally verified by comparison with a well-established BSS based on a 11 mm (diameter) × 3 mm (thickness) 6LiI(Eu) scintillator. The comparison was performed in the 14 MeV and 2.9 MeV neutron fields produced at the Frascati Neutron Generator. The proposed spectrometer can constitute a valuable tool for operational neutron dosimetry.
DOI: 10.1209/0295-5075/134/42001
2021
Cited 4 times
NCT-WES: A new single moderator directional neutron spectrometer for neutron capture therapy. Experimental validation
A directional neutron spectrometer called NCT-WES (Neutron Capture Therapy Wide Energy Spectrometer), conceived as a spectrometric beam monitor in neutron capture therapy, was designed and prototyped. As other types of single moderator neutron spectrometers, NCT-WES condenses the functionality of Bonner Spheres in a single moderator embedding multiple thermal neutron detectors in previously optimized positions. NCT-WES is a polyethylene cylinder with 36 cm diameter and 41.5 cm height. To achieve a sharply directional response, the sensitive part is shielded with a thick barrier made of polyethylene and borated rubber, except in the direction identified by the collimating aperture. The size, geometry, materials and detector locations were previously optimized to emphasise the spectrometric capability in the epithermal range. TNPD-type thermal neutron detectors, consisting of 1 cm2 silicon p-i-n diodes covered with 6 LiF are used as internal thermal neutron detectors. The simulation model of NCT-WES was experimentally verified by exposing the prototype in the reference neutron field of 241 Am-Be available at the Politecnico di Milano. The count rate in the NCT-WES internal detectors, as calculated from the simulation model, coincided with the experimental ones within about 2%, confirming the high degree of accuracy of the NCT-WES simulation model. Aspects related to the future use of NCT-WES in therapeutic neutron beams are finally discussed.
DOI: 10.1088/1748-0221/16/11/p11025
2021
Cited 4 times
First results with the ANET Compact Thermal Neutron Collimator
This paper presents the first determination of the spatial resolution of the ANET Compact Neutron Collimator, obtained with a measuring campaign at the LENA Mark-II TRIGA reactor in Pavia. This novel collimator consists of a sequence of collimating and absorbing channels organised in a chessboard-like geometry. It has a scalable structure both in length and in the field of view. It is characterized by an elevated collimation power within a limited length. Its scalability and compactness are added values with respect to traditional collimating system. The prototype tested in this article is composed of 4 concatenated stages, each 100mm long, with a channel width of 2.5mm, delivering a nominal L/D factor of 160. This measuring campaign illustrates the use of the ANET collimator and its potential application in neutron imaging for facilities with small or medium size neutron sources.
DOI: 10.3390/pr8050558
2020
Cited 4 times
Synthesis and Characterization of New Lithium and Boron Based Metal Organic Frameworks with NLO Properties for Application in Neutron Capture Therapy
In this work, we synthetized and characterized new crystalline materials with theranostic properties, i.e., they can be used both as bio-sensors and for “drug delivery”. The two solid crystalline compounds studied are Metal Organic Frameworks and have formulas Li[(C6H12O6)2B]·2H2O and Li[(C4H2O6)2B]·5.5H2O. They can be synthetized both with natural isotopes of Li and B or with 6Li and 10B isotopes, that can be explored for Neutron Capture Therapy (NCT) for anti-cancer treatment. The presence of chiral organic molecules, such as mannitol and tartaric acid, provides the NLO property to the crystals and thus their capability to generate the Second Harmonic, which is useful for applications as bio-sensors. The two compounds were characterized with X-ray Diffraction and the Second Harmonic Generation (SHG) responses were estimated by theoretical calculations, and the results were compared with experimental measurements of powdered samples. In order to test the behavior of such compounds under thermal neutron irradiation, we preliminary exposed one of the two compounds in the e_LiBANS facility at the Torino Physics Department. Preliminary results are reported.
DOI: 10.1080/01443615.2022.2058356
2022
Open issues in management of carbon monoxide poisoning in pregnancy: practical suggestions
Carbon monoxide (CO) poisoning during pregnancy may cause deleterious effects to the fetus. Hyperbaric oxygen therapy (HBO) in pregnancy is proven to be safe and it is considered to be beneficial, reducing the severity of the fetal injuries. However, a number of issues are still to be discussed, among them the question of the carboxyhemoglobin (COHb) levels that trigger HBO therapy in pregnant CO poisoned patients. In this letter we report some practical suggestions for organizations wishing to develop their own protocols.
DOI: 10.3390/electronics11111737
2022
aRTIC GAN: A Recursive Text-Image-Conditioned GAN
Generative Adversarial Networks have recently demonstrated the capability to synthesize photo-realistic real-world images. However, they still struggle to offer high controllability of the output image, even if several constraints are provided as input. In this work, we present a Recursive Text-Image-Conditioned GAN (aRTIC GAN), a novel approach for multi-conditional image generation under concurrent spatial and text constraints. It employs few line drawings and short descriptions to provide informative yet human-friendly conditioning. The proposed scenario is based on accessible constraints with high degrees of freedom: sketches are easy to draw and add strong restrictions on the generated objects, such as their orientation or main physical characteristics. Text on its side is so common and expressive that easily enforces information otherwise impossible to provide with minimal illustrations, such as objects components color, color shades, etc. Our aRTIC GAN is suitable for the sequential generation of multiple objects due to its compact design. In fact, the algorithm exploits the previously generated image in conjunction with the sketch and the text caption, resulting in a recurrent approach. We developed three network blocks to tackle the fundamental problems of catching captions’ semantic meanings and of handling the trade-off between smoothing grid-pattern artifacts and visual detail preservation. Furthermore, a compact three-task discriminator (covering global, local and textual aspects) was developed to preserve a lightweight and robust architecture. Extensive experiments proved the validity of aRTIC GAN and show that the combined use of sketch and description allows us to avoid explicit object labeling.
DOI: 10.1103/physrevd.85.052008
2012
Cited 3 times
Angular correlations in three-jet events inepcollisions at HERA
Three-jet production in deep inelastic $ep$ scattering and photoproduction was investigated with the ZEUS detector at HERA using an integrated luminosity of up to $127\text{ }\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$. Measurements of differential cross sections are presented as functions of angular correlations between the three jets in the final state and the proton-beam direction. These correlations provide a stringent test of perturbative QCD and show sensitivity to the contributions from different color configurations. Fixed-order perturbative calculations assuming the values of the color factors ${C}_{F}$, ${C}_{A}$, and ${T}_{F}$ as derived from a variety of gauge groups were compared to the measurements to study the underlying gauge group symmetry. The measured angular correlations in the deep inelastic $ep$ scattering and photoproduction regimes are consistent with the admixture of color configurations as predicted by SU(3) and disfavour other symmetry groups, such as $\mathrm{SU}(N)$ in the limit of large $N$.
DOI: 10.1016/j.physletb.2004.10.059
2005
Cited 5 times
Coherent soft particle production in Z decays into three jets
Low-energy particle production perpendicular to the event plane in three-jet events produced in Z decays in e+e− annihilation is measured and compared to that perpendicular to the event axis in two-jet events. The topology dependence of the hadron production ratio is found to agree with a leading-order QCD prediction. This agreement and especially the need for the presence of a destructive interference term gives evidence for the coherent nature of gluon radiation. Hadron production in three-jet events is found to be directly proportional to a single topological scale function of the inter-jet angles. The slope of the dependence of the multiplicity with respect to the topological scale was measured to be 2.211±0.014(stat.)±0.053(syst.) in good agreement with the expectation given by the colour-factor ratio CA/CF=9/4. This result strongly supports the assumption of local parton–hadron duality, LPHD, at low hadron momentum.
DOI: 10.1016/j.nima.2018.06.053
2018
Cited 3 times
Neutron spectrometry of a liquid Lithium based (p, n) beam at SARAF facility using the broad-energy range directional spectrometer CYSP
An intense neutron beam produced via 7Li(p, n)7Be reaction on a newly developed high-power liquid Lithium target (LiLiT) is available at SARAF (Soreq Applied Research Accelerator Facility) facility, Israel. Its spectrum was determined using the CYSP (CYlindrical SPectrometer), a new directional neutron spectrometer which incorporates the functionality of the Bonner spheres in a single cylindrical moderator. The advantages of this spectrometer are that the neutron spectrum is derived in only one exposure, and that its directional response is not affected by room- and air-scattered neutrons. The data from the CYSP spectrometer were analysed using the FRUIT unfolding code.
DOI: 10.1109/nssmic.2017.8533035
2017
Cited 3 times
Developments in the FBK Production of Ultra -Fast Silicon Detectors
In this contribution we present new developments in the production of Ultra Fast Silicon Detectors (UFSD) at Fondazione Bruno Kessler (FBK) in Trento, Italy. FBK after having in 2016 a successfully first production of UFSD sensors 300-micrometer thick, has produced in 2017 its first 50-micrometer thick UFSD sensors. These sensors use high resistivity Silicon on Silicon substrate and have different doping profile configurations of the gain layer based on Boron, Gallium, Carbonated Boron and Carbonated Gallium to obtain a controlled multiplication mechanism. The motivation of variety of gain layers it is to identify the most radiation hard technology to be employed in the production of UFSD for applications in high-radiation environments.
DOI: 10.1016/j.nima.2019.163154
2020
Cited 3 times
The e_LiBANS facility: A new compact thermal neutron source based on a medical electron LINAC
A new photonuclear thermal neutron facility has been developed at the Physics Department of University of Torino. The facility is based on a medical electron LINAC coupled to a compact converter and moderator assembly. A homogeneous thermal neutron radiation field of the order of 106 cm−2s−1 is achievable in the enclosed irradiation cavity with low gamma and fast neutron contaminations. Its intensity can be tuned varying the LINAC current. These characteristics make the source appropriate for several applications such as detectors development, material studies and BNCT preclinical research. This work describes the project and the experimental characterization of the facility. This includes the measurement of the thermal neutron fluence rate, the determination of the neutron energy spectrum and of the thermal neutron field uniformity and the evaluation of the gamma contamination.
2009
Cited 3 times
Psicologia Ambientale e Architettonica
DOI: 10.1016/j.nuclphysbps.2007.08.015
2007
Cited 3 times
The GNAM system in the ATLAS online monitoring framework
ATLAS [ATLAS Collaboration, “ATLAS Technical Proposal”, CERN/LHHCC/94-43, LHCC/P2, CERN, Geneva, Switzerland, 1994] is one of the four experiments under construction along the Large Hadron Collider (LHC) ring, which will produce interactions at a center of mass energy of 14 TeV at 40 MHz rate. The detector consists of more than 140 million electronic channels. The challenging experimental environment and the extreme detector complexity impose the necessity of a common scalable distributed monitoring framework, which can be tuned for the optimal use by different ATLAS detectors at the various levels of the ATLAS data flow.
DOI: 10.3233/jnr-220028
2023
Experimental results of the first ANET resolution campaign with the compact neutron collimator
This paper presents the first determination of the improvement in beam divergence when including the ANET Compact Neutron Collimator on an existing thermal neutron beam, obtained with a measuring campaign at the LENA Mark-II TRIGA reactor in Pavia. This novel collimator consists of a sequence of collimating and absorbing channels organised in a chessboard-like geometry. It has a scalable structure both in length and in the field of view. It is characterized by an elevated collimation power within a limited length. Its scalability and compactness are added values with respect to traditional collimating system. The prototype tested in this article is composed of 4 concatenated stages, each 100 mm long, with a channel width of 2.5 mm, delivering a nominal L/D factor of 160. This measuring campaign illustrates the use of the ANET collimator and its potential application in ne
DOI: 10.1016/j.nima.2022.167742
2023
First neutron tomography with the novel ANET Compact Neutron Collimator
This paper presents the first application of the novel ANET Compact Neutron Collimator to a tomographic study. The ANET collimator consists of a structure were collimating and absorbing channels are alternated in a chessboard-like geometry. It is characterised by an elevated collimation power within a limited length and presents a scalable structure both in length and in field of view. The first tomography with this collimator has been performed at the Paul Scherrer Institute, at the BOA beamline, on two small objects chosen for their different scattering properties: an iron fibula, circa X century, and an Afghan lapis lazuli. The result of the tomographic reconstruction is described in this paper.
DOI: 10.1016/j.nima.2022.167816
2023
Silicon sensors with resistive read-out: Machine Learning techniques for ultimate spatial resolution
Resistive AC-coupled Silicon Detectors (RSDs) are based on the Low Gain Avalanche Diode (LGAD) technology, characterized by a continuous gain layer, and by the innovative introduction of resistive read-out. Thanks to a novel electrode design aimed at maximizing signal sharing, RSD2, the second RSD production by Fondazione Bruno Kessler (FBK), achieves a position resolution on the whole pixel surface of about 8 $\mu m$ for 200-$\mu m$ pitch. RSD2 arrays have been tested using a Transient Current Technique setup equipped with a 16-channel digitizer, and results on spatial resolution have been obtained with machine learning algorithms.
DOI: 10.48550/arxiv.2301.07749
2023
Improved methodologies to study the performance of the ANET Compact Neutron Collimator
The ANET project aims at developing 2D compact neutron collimators for neutron imaging applications. The results of the ANET collimator performances, presented in this communication, are based on data collected at the FISH beamline at TU-Delft. Two independent methods to evaluate the neutron radiography resolution are described and discussed, as well as a comparison of the beam divergence with or without the ANET collimator.
DOI: 10.48550/arxiv.2302.14651
2023
Study and perspective on neutron beam divergence improvement achievable by the combination of two or more neutron collimating systems
This communication presents the results obtained at an experimental campaign at PSI BOA beamline using the combination of the ANET Compact Neutron Collimator (CNC) with the actual BOA pin-hole system. Through extensive resolution campaigns, it has been possible to quantify and understand the effects of improvement on the beam divergence when combining the two collimating systems. A new theoretical approach to this problem is described and discussed. The effect is expected not to be limited to the specific case that has been studied at PSI BOA but to have a more general validity for neutron collimation systems.
DOI: 10.1016/j.nima.2023.168260
2023
Improved methodologies to study the performance of the ANET Compact Neutron Collimator
The ANET project aims at developing 2D compact neutron collimators for neutron imaging applications. The results of the ANET collimator performances, presented in this communication, are based on data collected at the FISH beamline at TU-Delft. Two independent methods to evaluate the neutron radiography resolution are described and discussed, as well as a comparison of the beam divergence with or without the ANET collimator.
DOI: 10.5216/ree.v25.73389
2023
Análise do nível de atividade física, depressão, ansiedade e estresse segundo o sexo em adolescentes escolares: estudo transversal
Objetivo: comparar o nível de atividade física e sintomas de depressão, ansiedade e estresse segundo o sexo em adolescentes escolares. Métodos: estudo transversal com estudantes do ensino médio de escolas públicas. Utilizou-se na coleta de dados: Questionário sociodemográfico e de estilo de vida, Questionário Internacional de Atividade Física (IPAQ) e Escala de Depressão, Ansiedade e Estresse para Adolescentes (EDAE-A). Testes qui-quadrado de Pearson ou exato de Fisher e o Modelo Linear Generalizado Univariado foram utilizados na análise. Resultados: participaram 516 adolescentes, 214 do sexo masculino e 302 do feminino. Ambos os sexos apresentam prática de atividades físicas menor que o recomendado para adolescentes. Participantes do sexo masculino apresentam maior prática de atividade física fora da escola em comparação aos do sexo feminino, predominando o futebol (33,0%). Participantes do sexo feminino apresentaram maior gravidade dos níveis de depressão (p = 0,002), ansiedade (p = 0,013) e estresse (p = 0,004) em comparação aos do sexo masculino (d de Cohen fraco). Conclusão: não há diferença do nível de atividade física em adolescentes escolares segundo o sexo. Adolescentes do sexo masculino apresentam maior prática de atividades físicas fora da escola, e adolescentes do sexo feminino apresentam maior gravidade dos níveis de depressão, ansiedade e estresse.
DOI: 10.5151/2594-360x-40263
2023
AGENTE DE SEGURANçA: PROTAGONISTA NA EVOLUçãO CULTURAL DA SEGURANçA NAS OPERAçõES LOGíSTICAS
DOI: 10.48550/arxiv.2309.11496
2023
Unveiling dark forces with the Large Scale Structure of the Universe
Cosmology offers opportunities to test Dark Matter independently of its interactions with the Standard Model. We study the imprints of long-range forces acting solely in the dark sector on the distribution of galaxies, the so-called Large Scale Structure (LSS). We derive the strongest constraint on such forces from a combination of Planck and BOSS data. Along the way we consistently develop, for the first time, the Effective Field Theory of LSS in the presence of new dynamics in the dark sector. We forecast that future surveys will improve the current bound by an order of magnitude.
DOI: 10.1088/1742-6596/2605/1/012012
2023
Study and perspective on neutron beam divergence improvement achievable by the combination of two or more neutron collimating systems
Abstract This communication presents the results obtained at an experimental campaign at PSI BOA beamline using the combination of the ANET Compact Neutron Collimator (CNC) with the actual BOA pin-hole system. Through extensive resolution campaigns, it has been possible to quantify and understand the effects of improvement on the beam divergence when combining the two collimating systems. A new theoretical approach to this problem is described and discussed. The effect is expected not to be limited to the specific case that has been studied at PSI BOA but to have a more general validity for neutron collimation systems.
DOI: 10.1007/978-3-031-45093-8_11
2023
Garment Industries: Its Impact on Economic Growth and Prevailing Challenges Towards Sustainability
The Bangladeshi garment industry is a result of a trade quota system that enabled a degree of economic growth, and also implies questionable social and environmental costs. To further explain the phenomenon of the Bangladeshi garment industry arousal as one of the leading ready garment manufacturers in the world, we will describe what conditions helped them to obtain the role they perform, and associated profitability in the global production network. Further, we will portray the evolution of the exports and its significance for economic growth. We will unveil some global criticisms to the fast fashion production under the lenses of expected sustainability, to finalize describing the general supply management challenges that commonly organizations face to implement successful changes.
DOI: 10.54033/cadpedv20n6-008
2023
Análise financeira e avaliação da pegada de carbono na implementação dos métodos construtivos em edificações
A análise da pegada de carbono de produtos e serviços tem sido demandada cada vez mais nos mais diversos segmentos de negócio com o objetivo de identificar os impactos ambientais, sociais e econômicos. Na construção civil existem vários métodos construtivos, cada um com suas características e matrizes construtivas, sendo assim possuem taxa de pegada de carbono diferente entre si. Com o objetivo de realizar uma análise econômica e de pegada de carbono, esse artigo traz resultados obtidos através de uma pesquisa com metodologia exploratório da taxa de emissão de CO₂ equivalente associada com o custo de implementação dos métodos construtivos de concreto armado com fechamento em alvenaria, Steel Frame e Wood Frame. O estudo revela que o sistema construtivo Wood Frame possui a menor taxa de emissão de CO₂ equivalente, porém o custo para a implementação do sistema construtivo de concreto armado com fechamento em alvenaria substancialmente inferior ao Wood Frame e Steel Frame.
DOI: 10.51891/rease.v9i11.12325
2023
A DEMOCRATIZAÇÃO DO ACESSO À INFORMAÇÃO COMO DIREITO CÍVICO AO CIDADÃO BRASILEIRO: A IMPORTÂNCIA DO AUTOCONHECIMENTO CÍVICO PARA O CIDADÃO BRASILEIRO
O acesso à informação ou educação cívica, propicia, além da participação nas discussões acerca dos negócios públicos, a cobrança na resolução de problemas gerais e coletivos, assim com o objeto de fazer o estudo exploratório de autores acerca do debate e com base em pesquisa de dados obtidos junto a sites das instituições governamentais e organizações da sociedade civil, conteúdo jornalístico, e legislação vigente, através de seus canais de acesso ao público. O estudo objetiva revisar a literatura, pesquisas, informativos oficiais e lei, com a finalidade de analisar os elementos que explicam porque o cidadão brasileiro ser informado sobre o acesso aos seus direitos básicos. Metodologicamente, trata-se de uma revisão integrativa, utilizando estudos indexados em bases de dados contidos na literatura e nos canais de informação de entes públicos e privados. Entre os resultados estão a análise de 19 estudos, sendo 4 artigos selecionados através do critério de inclusão e exclusão onde é apontado que a democratização do acesso é existente, porém limitado em seu acesso, sem ações de incentivo para o alcance e usufruto das informações. O estudo mostrou que o direito à informação transcende em garantir o acesso dos cidadãos e além de incluir, garantir e fornecer meios e condições para que o acesso à informação seja legítimo.
DOI: 10.18616/rsp.v7i2.8263
2023
ENSINAR E APRENDER: PANORAMA DOS ESTUDOS SOBRE A DIDÁTICA NO CONTEXTO DA EDUCAÇÃO BÁSICA
O presente estudo buscou problematizar alguns elementos imprescindíveis em torno da didática e o processo de formação docente no contexto da Educação Básica, visto que o conhecimento desta preconiza a excelência da prática docente, oportunizando então, um processo de ensino aprendizagem significativo para os alunos. Nesse sentido, o objetivo geral se concentra em compreender a importância da didática como possibilidade de articulação entre o ensinar e o aprender a partir de um panorama dos estudos sobre a didática no contexto da educação básica. O objetivo geral se desdobra nos seguintes objetivos específicos: investigar as produções do ensino aprendizado em torno da didática, identificar as contribuições da didática para o processo de ensino e aprendizagem e situar a didática como campo de conhecimento relevante à prática pedagógica. A pesquisa teve uma abordagem qualitativa a partir de uma pesquisa bibliográfica. Os dados foram analisados à luz de Libâneo (1990), Vasconcellos (2014), dentre outros, além de documentos como Currículo do Território Catarinense (2019) e a Lei de Diretrizes e Bases da Educação Nacional - LDBEN (1994). Os estudos tratam, dentre outras questões, sobre a importância do processo de ensino e aprendizagem como ato intencional e sistemático, que se reinventa e ocorre de acordo com as especificidades, espaço e tempo de cada sujeito. Nesse sentido, entendem a didática, como questão imprescindível para que ocorra a ação-reflexão-ação efetivando a apropriação do conhecimento de maneira mais significativa. Além disso, abordam a importância da formação inicial e continuada, não somente para a resolução de problemas, mas também, para oportunizar novas estratégias de ensinar e aprender visando o desenvolvimento cognitivo, social, cultural, entre outros. Outro ponto fundamental destacado pelos autores, diz respeito a importância de documentos norteadores e vertentes de conteúdos transversais e interculturais, questionando a produção do conhecimento e trazendo para o contexto a didática numa perspectiva não-fascista e decolonial.&#x0D; Palavras chave: Ensino e aprendizagem; Didática; Formação de professores; Educação Básica.