M. Kaya

We observe a signal for the doubly charmed baryon Xi(+)(cc) in the charged decay mode Xi(+)(cc)-->Lambda(+)(c)K-pi(+) in data from SELEX, the charm hadroproduction experiment at Fermilab. We observe an excess of 15.9 events over an expected background of 6.1+/-0.5 events, a statistical significance of 6.3sigma. The observed mass of this state is 3519+/-1 MeV/c(2). The Gaussian mass width of this state is 3 MeV/c(2), consistent with resolution; its lifetime is less than 33 fs at 90% confidence.

We observe a signal for the doubly charmed baryon Ξcc+ in the decay mode Ξcc+→pD+K− to complement the previous reported decay Ξcc+→Λc+K−π+ in data from SELEX, the charm hadroproduction experiment at Fermilab. In this new decay mode we observe an excess of 5.62 events over a combinatoric background estimated by event mixing to be 1.38±0.13 events. The mixed background has Gaussian statistics, giving a signal significance of 4.8σ. The Poisson probability that a background fluctuation can produce the apparent signal is less than 6.4×10−4. The observed mass of this state is 3518±3MeV/c2, consistent with the published result. Averaging the two results gives a mass of 3518.7±1.7MeV/c2. The observation of this new weak decay mode confirms the previous SELEX suggestion that this state is a double charm baryon. The relative branching ratio for these two modes is 0.36±0.21.

We report the first observation of a charm-strange meson D(+)(sJ)(2632) at a mass of 2632.5+/-1.7 MeV/c(2) in data from SELEX, the charm hadro-production experiment E781 at Fermilab. This state is seen in two decay modes, D(+)(s)eta and D0K+. In the D(+)(s)eta decay mode we observe a peak with 101 events over a combinatoric background of 54.9 events at a mass of 2635.4+/-3.3 MeV/c(2). There is a corresponding peak of 21 events over a background of 6.9 at 2631.5+/-2.0 MeV/c(2) in the decay mode D0K+. The decay width of this state is <17 MeV/c(2) at 90% confidence level. The relative branching ratio Gamma(D0K+)/Gamma(D(+)(s)eta) is 0.14+/-0.06. The mechanism that keeps this state narrow is unclear. Its decay pattern is also unusual, being dominated by the D(+)(s)eta decay mode.

We report on the test beam results and calibration methods using high energy electrons, pions and muons with the CMS forward calorimeter (HF). The HF calorimeter covers a large pseudorapidity region ( $3\leq|\eta|\leq5$ ), and is essential for a large number of physics channels with missing transverse energy. It is also expected to play a prominent role in the measurement of forward tagging jets in weak boson fusion channels in Higgs production. The HF calorimeter is based on steel absorber with embedded fused-silica-core optical fibers where Cherenkov radiation forms the basis of signal generation. Thus, the detector is essentially sensitive only to the electromagnetic shower core and is highly non-compensating (e/h≈5). This feature is also manifest in narrow and relatively short showers compared to similar calorimeters based on ionization. The choice of fused-silica optical fibers as active material is dictated by its exceptional radiation hardness. The electromagnetic energy resolution is dominated by photoelectron statistics and can be expressed in the customary form as $\frac{a}{\sqrt{E}}\oplus{b}$ . The stochastic term a is 198% and the constant term b is 9%. The hadronic energy resolution is largely determined by the fluctuations in the neutral pion production in showers, and when it is expressed as in the electromagnetic case, a = 280% and b = 11%.

Extensive measurements have been made with pions, electrons and muons on four production wedges of the compact muon solenoid (CMS) hadron barrel (HB) calorimeter in the H2 beam line at CERN with particle momenta varying from 20 to 300 GeV/c. The time structure of the events was measured with the full chain of preproduction front-end electronics running at 34 MHz. Moving-wire radioactive source data were also collected for all scintillator layers in the HB. The energy dependent time slewing effect was measured and tuned for optimal performance.

The Sigma^- mean squared charge radius has been measured in the space-like Q^2 range 0.035-0.105 GeV^2/c^2 by elastic scattering of a Sigma^- beam off atomic electrons. The measurement was performed with the SELEX (E781) spectrometer using the Fermilab hyperon beam at a mean energy of 610 GeV/c. We obtain <r^2> = (0.61 +/- 0.12 (stat.) +/- 0.09 (syst.)) fm^2. The proton and pi^- charge radii were measured as well and are consistent with results of other experiments. Our result agrees with the recently measured strong interaction radius of the Sigma^-.

We present data from Fermilab experiment E781 (SELEX) on the hadroproduction asymmetry for Λ̄c− compared to Λc+ as a function of xF, and on pt2 distributions for Λc+. These data were measured in the same apparatus using incident π−, Σ− beams at 600 GeV/c and proton beam at 540 GeV/c. The asymmetry is studied as a function of xF. In the forward hemisphere with xF⩾0.2 both baryon beams exhibit very strong preference for producing charm baryons rather than charm antibaryons, while the pion beam asymmetry is much smaller. In this energy regime the results show that beam fragments play a major role in the kinematics of Λc formation, as suggested by the leading quark picture.

Total cross sections for Σ− and π− on beryllium, carbon, polyethylene and copper as well as total cross sections for protons on beryllium and carbon have been measured in a broad momentum range around 600GeV/c . These measurements were performed with a transmission technique in the SELEX hyperon-beam experiment at Fermilab. We report on results obtained for hadron–nucleus cross sections and on results for σtot(Σ−N) and σtot(π−N) , which were deduced from nuclear cross sections.

We report new precision measurements of the lifetimes of the ${\ensuremath{\Lambda}}_{c}^{+}$ and ${D}^{0}$ from SELEX, the charm hadroproduction experiment at Fermilab. Based upon 1630 ${\ensuremath{\Lambda}}_{c}^{+}$ and 10 210 ${D}^{0}$ decays we observe lifetimes of $\ensuremath{\tau}[{\ensuremath{\Lambda}}_{c}^{+}]\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}198.1\ifmmode\pm\else\textpm\fi{}7.0\ifmmode\pm\else\textpm\fi{}5.6\mathrm{fs}$ and $\ensuremath{\tau}[{D}^{0}]\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}407.9\ifmmode\pm\else\textpm\fi{}6.0\ifmmode\pm\else\textpm\fi{}4.3\mathrm{fs}$.

Coherent Λπ− production on Pb of 600 GeV Σ− hyperons has been studied with the SELEX facility at Fermilab. Using the Primakoff formalism, we set a 90% CL upper limit on the radiative decay width Γ[Σ(1385)−→Σ−γ]<9.5 keV, and estimate the cross section for γΣ−→Λπ− at s≈1.385 GeV to be 56±16 μb.

We show the test results for TOF resolution and μ/e separation capabilities of a prototype element (Iori and Sergi, 2008 [1]), intended for deployment in an array capable of measuring large zenith angle cosmic rays as well as detecting the signature of Ultra High Energy tau neutrino interactions using the Earth skimming strategy (Fargion et al., 2004 [2], Feng et al., 2002 [3], Beacom et al., 2003 [4], Zas, 2005 [5]). The module was designed to recognize single particles and determine the direction of motion (up/down) and measure the trajectory angles. It uses two pairs of scintillator counters, named towers, each composed by two tiles (20×20 cm2, 1.4 cm thick), separated by 160 cm. Each tile is read by one low voltage R5783 Hamamatsu photomultiplier (PMT). Two PMT boxes are attached to a metal structure that defines the axis of the array. Each tile is embedded in a PVC box which also contains the PMT. The PMT has excellent time resolution (≈400ps) for good TOF precision. The PMT signal was digitized by the MATAQ board in coincidence with KASCADE-GRANDE (KG) shower Delagnes and Breton, 2001 [6].

Coherent π+π−π− production in the interactions of a beam of 600GeV π− mesons with C, Cu and Pb nuclei has been studied with the SELEX facility (Experiment E781 at Fermilab). The a2(1320) meson signal has been detected in the Coulomb (low q2) region. The Primakoff formalism used to extract radiative decay width of this meson yields Γ=284±25±25keV, which is the most precise measurement to date.

We report a precise measurement of the D±s meson lifetime. The data were taken by the SELEX experiment (E781) spectrometer using 600 GeV/c Σ−, π− and p beams. The measurement has been done using 918 reconstructed D±s. The lifetime of the D±s is measured to be 472.5±17.2±6.6 fs, using K∗(892)0K± and φπ± decay modes. The lifetime ratio of Ds± to D0 is 1.145±0.049.

We report the measurement of the one-dimensional charged kaon correlation functions using 600GeV/c Σ−, π− and 540GeV/c p beams from the SELEX (E781) experiment at the Fermilab Tevatron. K±K± correlation functions are studied for three transverse pair momentum, kT, ranges and parameterized by a Gaussian form. The emission source radii, R, and the correlation strength, λ, are extracted. The analysis shows a decrease of the source radii with increasing kaon transverse pair momentum for all beam types.

Abstract We present the preliminary test results of the prototype detector, working at Sphinx Observatory Center, Jungfraujoch (~3800 m a.s.l.) HFSJG – Switzerland. This prototype detector is designed to measure large zenith angle showers produced by high energy neutrino interactions in the Earth crust. This station provides us an opportunity to understand if the prototype detector works safely (or not) under hard environmental conditions (the air temperature changes between −25 °C and −5 °C). The detector prototype is using silicon photomultiplier (SiPM) produced by SensL and DRS4 chip as read-out part. Measurements at different temperature at fixed bias voltage (~29.5 V) were performed to reconstruct tracks by Time Of Flight.

The production of Ds− relative to Ds+ as a function of xF with 600 GeV/c Σ− beam is measured in the interval 0.15<xF<0.7 by the SELEX (E781) experiment at Fermilab. The integrated charge asymmetries with 600 GeV/c Σ− beam (0.53±0.06) and π− beam (0.06±0.11) are also compared. The results show the Σ− beam fragments play a role in the production of Ds−, as suggested by the leading quark model.

We report the first observation of two Cabibbo-suppressed decay modes, Ξc+→Σ+π−π+ and Ξc+→Σ−π+π+. We observe 59±14 over a background of 87, and 22±8 over a background of 13 events, respectively, for the signals. The data were accumulated using the SELEX spectrometer during the 1996–1997 fixed target run at Fermilab, chiefly from a 600GeV/c Σ− beam. The branching ratios of the decays relative to the Cabibbo-favored Ξc+→Ξ−π+π+ are measured to be B(Ξc+→Σ+π−π+)/B(Ξc+→Ξ−π+π+)=0.48±0.20, and B(Ξc+→Σ−π+π+)/B(Ξc+→Ξ−π+π+)=0.18±0.09, respectively. We also report branching ratios for the same decay modes of the Λc+ relative to Λc+→pK−π+.

A new Radio-frequency quadrupole (RFQ), which operates at 800 MHz high frequency and will enable to accelerate of the proton beam efficiently was designed at KAHVELab (Kandilli Detector, Accelerator and Instrumentation Laboratory) at Bo\u{g}azi\c{c}i University in \.Istanbul, Turkey. The so-called PTAK-RFQ, which consists of two modules with a total length of less than one meter will accelerate protons to 2 MeV at the Proton Testbeam at the Kandilli campus, known as the PTAK project. The prototype of the first module of the 800 MHz PTAK-RFQ (called the PTAK-RFQ module 0), which captures and bunches the proton beam injected from the ion source was fabricated by a local manufacturer from ordinary copper material. The PTAK-RFQ module 0 was subjected to various tests to ensure that its mechanics, pressure, field distribution, and frequency are operationally adjusted. The facilitating solutions emerging from the detailed testing of the PTAK-RFQ module 0 will ultimately guide all mechanical, vacuum, rf testing, final design, and manufacturing processes of the final PTAK-RFQ. The PTAK-RFQ module 0 was first subjected to vacuum tests and then to detailed vacuum leak tests. Subsequently, low-power rf measurements were performed for tuning of field and frequency. The tuning algorithm developed by CERN was optimized for 16 tuners and 6 test field points to be adjusted to the PTAK-RFQ module 0 to the desired field distribution. The tuning algorithm is based on a response matrix, whose inputs are created by bead-pull measurements of individual tuner movements. The tuning algorithm gives some predictions for corrective tuner movements to achieve desired field distribution. In the framework of all these RF tuning processes, the field distribution was tuned through the tuning algorithm and then the frequency was tuned manually.

The hearing loss of almost half a billion people is commonly treated with hearing aids. However, current hearing aids often do not work well in real-world noisy environments. We present a deep learning based denoising system that runs in real time on iPhone 7 and Samsung Galaxy S10 (25ms algorithmic latency). The denoised audio is streamed to the hearing aid, resulting in a total delay of around 75ms. In tests with hearing aid users having moderate to severe hearing loss, our denoising system improves audio across three tests: 1) listening for subjective audio ratings, 2) listening for objective speech intelligibility, and 3) live conversations in a noisy environment for subjective ratings. Subjective ratings increase by more than 40%, for both the listening test and the live conversation compared to a fitted hearing aid as a baseline. Speech reception thresholds, measuring speech understanding in noise, improve by 1.6 dB SRT. Ours is the first denoising system that is implemented on a mobile device, streamed directly to users' hearing aids using only a single channel as audio input while improving user satisfaction on all tested aspects, including speech intelligibility. This includes overall preference of the denoised and streamed signal over the hearing aid, thereby accepting the higher latency for the significant improvement in speech understanding.

The hearing loss of almost half a billion people is commonly treated with hearing aids. However, current hearing aids often do not work well in real-world noisy environments. We present a deep learning based denoising system that runs in real time on iPhone 7 and Samsung Galaxy S10 (25 ms algorithmic latency). The denoised audio is streamed to the hearing aid, resulting in a total delay of around 65–75 ms, depending on the phone. In tests with hearing aid users having moderate to severe hearing loss, our denoising system improves audio across three tests: 1) listening for subjective audio ratings, 2) listening for objective speech intelligibility, and 3) live conversations in a noisy environment for subjective ratings. Subjective ratings increase by more than 40%, for both the listening test and the live conversation compared to a fitted hearing aid as a baseline. Speech reception thresholds, measuring speech understanding in noise, improve by 1.6 dB SRT. Ours is the first denoising system that is implemented on a mobile device, streamed directly to users’ hearing aids using only a single channel as audio input while improving user satisfaction on all tested aspects, including speech intelligibility. This includes overall preference of the denoised and streamed signal over the hearing aid, thereby accepting the higher latency for the significant improvement in speech understanding.

We present results from tests performed at Karlsruhe Institute of Technology (KIT) and at FermiLab Meson Test Beam Facility (FNAL) to study electron-muon separation, time of flight resolution and the acceptance for a new EAS detector concept. The very good time resolution and adjustable orientation of the detector permit to separate upward-moving tracks from downward tracks at any orientation with high efficiency. With these performances the detector can measure interaction products from cosmic neutrinos with zenith angles > 90 degrees, defining a chord through the earth as the interaction path. This kind of detector using SiPM will be a part of a large area array (several square kilometer) designed to measure UHE neutrinos (0.01-100 EeV).

Pion virtual compton scattering ͑VCS͒ via the reaction Ϫ e→ Ϫ e␥ was observed in the Fermilab E781 SELEX experiment.SELEX used a 600 GeV/c Ϫ beam incident on target atomic electrons, detecting the incident Ϫ and the final state Ϫ , electron and ␥.Theoretical predictions based on chiral perturbation theory are incorporated into a Monte Carlo simulation of the experiment and are compared to the data.The number of reconstructed events ͑ϭ9͒ and their distribution with respect to the kinematic variables ͑for the kinematic region studied͒ are in reasonable accord with the predictions.The corresponding Ϫ VCS experimental cross section is ϭ38.8Ϯ13nb, in agreement with the theoretical expectation of ϭ34.7 nb.

The cosmic ray spectrum extends to energies above 10^20 eV. In direct production or acceleration models, as well as by photo-pion interaction high energy cosmic ray flux must contain neutrinos and photons. The latter are absorbed by cosmic radiations while neutrinos are not. The need of a Neutrino Astronomy is compelling. In this paper a study of a detector array designed to measure horizontal tau air-showers emerging from the ground, produced by nu_tau interactions with the Earth's crust, is presented. Each array unit is composed of a pair of scintillator tiles mounted on a frame with a front field of view of about 0.1 sr, optimized to distinguish between up-going and down-going crossing particles by their time of flight. The detector array sensitivity, the size of the array and the tau shower identification are discussed. Because of the almost complete mixing of nu_mu to nu_tau the ultrahigh energy neutrino tau and its minimal consequent tau-airshower rate is estimated; assuming that the neutrino energy spectrum follows a Fermi-like power law E^-2, the sensitivity with 3 years of observation is estimated to be about 60 eV cm^-2s^-1sr^-1 in the energy range 10^{17-20} eV. This value would provide competitive upper limit with present and future experiments. We found also that, in the same time, this system can observe about one GZK neutrino event per km^2.

We show that ${\ensuremath{\Sigma}}^{+}$ hyperons produced by 800 GeV/c protons on targets of Be and Cu have significant polarizations (15--20%). These polarizations persist at values of ${p}_{t}\ensuremath{\approx}2\text{ }\text{ }\mathrm{G}\mathrm{e}\mathrm{V}/\mathrm{c}$ and a wide range of ${x}_{F}$. The polarizations from the Cu target are consistently less than from Be. The average ratio of the ${\ensuremath{\Sigma}}^{+}$ polarization from Cu to that from Be is $0.68\ifmmode\pm\else\textpm\fi{}0.08$.

In preparation for collecting proton-proton collisions from the LHC at a center-of-mass energy of 13 TeV and rate of 40MHz with increasing instantaneous luminosity, the CMS collaboration prepared an array of triggers utilizing jets and missing transverse energy for searches for new physics at the energy frontier as well as for SM precision measurements. The CMS trigger system must be able to sift through the collision events in order to extract events of interest at a rate of 1kHz, applying sophisticated algorithms adapted for fast and effective operation. Particularly important is the calibration of the trigger objects, as corrections to the measured energy may be substantial. Equally important is the development of improved reconstruction algorithms to mitigate negative effects due to high numbers of overlapping proton-proton collisions and increased levels of beam-related effects. Work by the CMS collaboration on upgrading the high-level trigger for jets and missing transverse energy for the upgraded LHC operation will be presented, along with the improved performance of these triggers.

Bu çalışmada, Atatürk Üniversitesi Astronomi ve Uzay Bilimleri Bölümü ile Astrofizik Araştırma ve Uygulama Merkezi (ATASAM) bünyesinde ortak tasarlanan kozmik ışın (müon) dedektörünün kurulum aşamaları ve ilk sonuçları sunulmaktadır. Bu kapsamda ilk ölçümler, 21- 30 Mayıs 2022 tarihleri arasında Erzurum Atatürk Üniversitesi yerleşkesinde bulunan ATA50 Teleskobu yakınında yapılmıştır. Dedektör sintilatörleri, Zenite bakacak şekilde (0°) yerleştirilmiştir. Alınan veriler, Python ve ROOT programları ile analiz edilmiştir. Bu sayede, ilk veriler 1885 metre rakıma sahip Atatürk Üniversitesi yerleşkesinin kozmik müon akısı olarak elde edilmiştir. Bölgenin akı değeri, literatürden alınan farklı irtifalardaki akı değerleri ile karşılaştırılmıştır. Böylece, Doğu Anadolu Gözlemevi (DAG) için sürekli kozmik ışın ölçümleri yapacak bir istasyon kurulumunun ilk çalışmaları tamamlanmıştır.

energy trigger for the $$\pi$$, K and p beams respectively. This is the world's largest sample of kaon induced $$D_s$$ mesons. This indicates an average $$\sigma$$ •B (normalizing B($$D_s \to tK^*K$$) to B($$D_s \to \phi \pi$$)) over the two modes of 0.036±0.015μb/nucleon, 0.044±0.018μb/nucleon and 0.035±0.025μb/nucleon for each of the three different beam particles respectively using $$A^{0.95 ± 0.05}$$ for $$X_F$$ > O. These values are consistent with recent measurements by the ACCMOR collaboration at CERN. The absolute cross sections for production of $$D_s$$ by each of the three beam particles are calculated using the world average of the branching ratio to the $$\phi \pi$$ decay mode. Assuming that all systematic errors cancel, the ratio of the K to $$\pi$$ absolute $$D_s$$ production cross section is found to be 1.2 ± 0.7 for $$X_F$$ > O. The $$X_F$$ and $PT^2$ distributions of the Ds mesons for all three beam particles are also presented. All of these results are compared to QCD predictions as well as the LUND Monte Carlo. The differential distributions are consistent to within errors with other experimental results. We find no evidence for a flavour dependence of the production of the $$D_s$$ meson in the total and differential cross sections.

A hodoscope system constructed with a scintillating fiber array and a multianode photomultiplier is described. The results of laboratory and beam tests on the hodoscope response, efficiency and spatial resolution are discussed.

The status of the multiwire proportional chambers in the FERMILAB E781 experiment and a general description of the readout system are given. This essay will describe the system of multiwire proportional chambers (MWPC) that are part of the Fermilab experiment E781 setup. Multiwire proportional chambers are often used in particle physics experiments because they can determine the position of charged particles very accurately (less than a millimeter). The E781 experiment which is also called SELEX (SEgmented LargE-X) is a spectrometer designed to study the production and decay of charmed baryons. MWPCs are part of the 3-stage charged particle spectrometer (Figure 1). Each spectrometer stage includes a bending magnet and chambers. More information about E781 experiment is given in the Appendix. In the following, some basic concepts of MWPCs will be given briefly. After that the multiwire proportional chambers (M1PWC and M3PWC) that are used in the E781 fixed target experiment will be described. Then a general description of the readout system for both M1PWC and M3PWC setups will follow. Finally the tests done on both sets of chambers will be explained in detail.