M. Menichelli

view Abstract Citations (122) References (13) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Observations of Cosmic-Ray Electrons and Positrons Using an Imaging Calorimeter Golden, R. L. ; Grimani, C. ; Kimbell, B. L. ; Stephens, S. A. ; Stochaj, S. J. ; Webber, W. R. ; Basini, G. ; Bongiorno, F. ; Massimo Brancaccio, F. ; Ricci, M. ; Ormes, J. F. ; Streitmatter, R. E. ; Papini, P. ; Spillantini, P. ; Brunetti, M. T. ; Codino, A. ; Menichelli, M. ; Salvatori, I. ; de Pascale, M. P. ; Morselli, A. ; Picozza, P. Abstract A ballon-borne magnet spectrometer system was flown for 5.5 hr at an altitude of more than 117,00 feet from Prince Albert, Saskatchewan (Canada), on 1989 September 5, when the Newark neutron monitor rate was 2952. The instrument was a modified version of the one used to observe antiprotons in 1979. The most significant modification was the addition of an imaging calorimeter, 7.33 radiation lengths thick. Inclusion of the calorimeter has significantly improved the ability to distinguish electrons and positrons from the other constituents of the cosmic rays. The absolute electron flux has been determined in the energy interval 1.3-26 GeV. The electron spectrum at the top of the atmosphere was found to be Je- = 177E-(3.15+/-0.13) electrons/ sq m/(sr s GeV) in the energy range 4.0-26 GeV. Below 4 GeV, the spectrum showed flattening, which is consistent with the effect of solar modulation. The e(+)/(e(+)+e(-)) ratio was found to be (0.11 +/- 0.03) in the energy range 5.2-13 GeV. Publication: The Astrophysical Journal Pub Date: December 1994 DOI: 10.1086/174951 Bibcode: 1994ApJ...436..769G Keywords: Cosmic Rays; Electron Spectroscopy; Electrons; Heat Measurement; Imaging Techniques; Positrons; Balloon-Borne Instruments; Calorimeters; Magnetic Spectroscopy; Spectrographs; Spectrometers; Astronomy; ELEMENTARY PARTICLES; INSTRUMENTATION: SPECTROGRAPHS; ISM: COSMIC RAYS full text sources ADS |

The Alpha Magnetic Spectrometer is a large acceptance cosmic-ray detector (0.5m2sr) designed to operate at an altitude of 400 km on the International Space Station. The AMS-02 silicon tracker contains 2264 silicon microstrip sensors (total active area 6.75m2). The internal alignment parameters of the assembled tracker have been determined on the ground with cosmic-ray muons. The alignment procedure is described and results for the alignment precision and position resolution are reported.

As part of a series of experiments to search for antimatter in cosmic rays, the New Mexico State University balloon-borne magnet spectrometer was configured for a flight to study positrons. Two completely new instruments, a transition radiation detector and a silicon-tungsten imaging calorimeter, were added to the magnet spectrometer. These two detectors provided a proton rejection factor better than 3 × 104. This instrument was flown from Fort Sumner, New Mexico, at an average depth of 4.5 g cm-2 of residual atmosphere for a period of 25 hr. We report here the measured fraction of positrons e+/(e+ + e-) from ~5 to 60 GeV at the top of the atmosphere. Our measurements do not show any compelling evidence for an increase in this ratio with energy, and our results are consistent with a constant fraction of 0.078 ± 0.016 over the entire energy region.

Beam test results of the radiation tolerance study of chemical vapour deposition (CVD) diamond against different particle species and energies is presented. We also present beam test results on the independence of signal size on incident particle rate in charged particle detectors based on un-irradiated and irradiated poly-crystalline CVD diamond over a range of particle fluxes from 2 kHz/cm2 to 10 MHz/cm2. The pulse height of the sensors was measured with readout electronics with a peaking time of 6 ns. In addition functionality of poly-crystalline CVD diamond 3D devices was demonstrated in beam tests and 3D diamond detectors are shown to be a promising technology for applications in future high luminosity experiments.

The antiproton-to-proton ratio, /p, in cosmic rays has been measured in the energy range 3.7-19 GeV. This measurement was carried out using a balloon-borne superconducting magnetic spectrometer along with a gas Cerenkov counter, an imaging calorimeter, and a time-of-flight scintillator system. The measured /p ratio was determined to be 1.24−0.51+0.68 × 10-4. The present result, along with other recent observations, shows that the observed abundances of antiprotons are consistent with models in which antiprotons are produced as secondaries during the propagation of cosmic rays in the Galaxy.

Abstract The characteristics of a hydrogenated amorphous silicon (a-Si:H) detector are presented here for monitoring in space solar flares and the evolution of strong to extreme energetic proton events. The importance and the feasibility to extend the proton measurements up to hundreds of MeV is evaluated. The a-Si:H presents an excellent radiation hardness and finds application in harsh radiation environments for medical purposes, for particle beam characterization and, as we propose here, for space weather science applications. The critical flux detection limits for X rays, electrons and protons are discussed.

We have determined the momentum spectrum and charge ratio of muons in the region from 250 MeV/c to 100 GeV/c using a superconducting magnetic spectrometer. The absolute differential spectrum of muons obtained in this experiment at 600 m above sea level is in good agreement with the previous measurements at sea level. The differential spectrum can be represented by a power law with a varying index, which is consistent with zero below 450 MeV/c and steepens to a value of −2.7 ± 0.1 between 20 and 100 GeV/c. The integral flux of muons measured in this experiment span a very large range of momentum and is in excellent agreement with the earlier results. The positive to negative muon ratio appears to be constant in the entire momentum range covered in this experiment within the errors and the mean value is 1.220 ± 0.044. The absolute momentum spectrum and the charge ratio measured in this experiment are also consistent with the theoretical expectations. This is the only experiment which covers a wide range of nearly 3 decades in momentum from a very low momentum.

The Alpha Magnetic Spectrometer is designed for a long duration measurement of the cosmic-ray spectra at an altitude of 400 km. The particle rigidity and specific energy loss are measured by a silicon tracker located in a 0.8 T field. Ground results for the position resolution, detection efficiency and charge determination for singly and doubly charged relativistic particles are presented and discussed in the context of the spaceborne detector.

This paper summarizes the performance characteristics of the balloon-borne magnet spectrometer operated by New Mexico State University's Particle Astrophysics Laboratory. Particular emphasis has been placed on the rigidity resolution, including both random and systematic errors of the magnetic spectrometer system. Measurement of the performance characteristics has been greatly enhanced through the use of an imaging calorimeter as an independent aid in the identification of cosmic rays.

Pixel detectors at HL-LHC experiments or other future experiments are facing new challenges, especially in terms of unprecedented levels of radiation and particle flux. This paper describes the progress made by the CHIPIX65 project of INFN for the development of a new generation readout ASIC using CMOS 65 nm technology.

This paper is a review of recent progress of RD53 Collaboration. Results obtained on the study of the radiation effects on 65 nm CMOS have matured enough to define first strategies to adopt in the design of analog and digital circuits. Critical building blocks and analog very front end chains have been designed, tested before and after 5–800 Mrad. Small prototypes of 64×64 pixels with complex digital architectures have been produced, and point to address the main issues of dealing with extremely high pixel rates, while operating at very small in-time thresholds in the analog front end. The collaboration is now proceeding at full speed towards the design of a large scale prototype, called RD53A, in 65 nm CMOS technology.

Objective. Microbeam radiation therapy (MRT) is an alternative emerging radiotherapy treatment modality which has demonstrated effective radioresistant tumour control while sparing surrounding healthy tissue in preclinical trials. This apparent selectivity is achieved through MRT combining ultra-high dose rates with micron-scale spatial fractionation of the delivered x-ray treatment field. Quality assurance dosimetry for MRT must therefore overcome a significant challenge, as detectors require both a high dynamic range and a high spatial resolution to perform accurately.Approach. In this work, a series of radiation hard a-Si:H diodes, with different thicknesses and carrier selective contact configurations, have been characterised for x-ray dosimetry and real-time beam monitoring applications in extremely high flux beamlines utilised for MRT at the Australian Synchrotron.Results. These devices displayed superior radiation hardness under constant high dose-rate irradiations on the order of 6000 Gy s-1, with a variation in response of 10% over a delivered dose range of approximately 600 kGy. Dose linearity of each detector to x-rays with a peak energy of 117 keV is reported, with sensitivities ranging from (2.74 ± 0.02) nC/Gy to (4.96 ± 0.02) nC/Gy. For detectors with 0.8μm thick active a-Si:H layer, their operation in an edge-on orientation allows for the reconstruction of micron-size beam profiles (microbeams). The microbeams, with a nominal full-width-half-max of 50μm and a peak-to-peak separation of 400μm, were reconstructed with extreme accuracy. The full-width-half-max was observed as 55 ± 1μm. Evaluation of the peak-to-valley dose ratio and dose-rate dependence of the devices, as well as an x-ray induced charge (XBIC) map of a single pixel is also reported.Significance. These devices based on novel a-Si:H technology possess a unique combination of accurate dosimetric performance and radiation resistance, making them an ideal candidate for x-ray dosimetry in high dose-rate environments such as FLASH and MRT.

Hydrogenated amorphous silicon (a-Si:H) has been proposed as a suitable material for particle detection applications thanks to its property to be deposited over a large area and above a variety of different substrates, including flexible materials. Moreover, the low cost and intrinsic radiation tolerance made this material appealing in applications where high fluences are expected, e.g. in high energy physics experiments. In order to optimize the device geometry and to evaluate its electrical behaviour in different operating conditions, a suitable Technology CAD (TCAD) design methodology can be applied. In this work, carried out in the framework of the HASPIDE INFN project, we propose an innovative approach to the study of charge transport within the material, using the state-of-the-art Synopsys Advanced TCAD Suite. Different custom mobility models have been devised and implemented within the code as external PMI (Physical Model Interfaces), starting from the Poole–Frenkel model and accounting for different dependencies on temperature and internal potential distribution, thus resulting in a new mobility model embedded within the code. Simple test structures, featuring p-i-n diodes have been simulated and compared to experimental data as a benchmark. The overall aim was to account for the effect of different biasing conditions (namely, different electrical potential and electric field distribution within the device) and operating conditions (e.g. temperature). This work fosters the use of commercially available TCAD suite such as Synopsys Sentaurus, largely diffused in the radiation detection scientific community, for the design and optimization of innovative a-Si:H devices for particle detection applications.

Hydrogenated amorphous silicon (a-Si:H) is a material having an intrinsically high radiation hardness that can be deposited on flexible substrates such as polyimide (PI). For these properties, a-Si:H can be used for the production of flexible sensors. a-Si:H sensors can be successfully utilized in dosimetry, beam monitoring for particle physics (X-ray, electron, gamma ray, and proton detection) and radiotherapy, radiation flux measurement for space applications (study of solar energetic particles and stellar events), and neutron flux measurements. In this article, we have studied the dosimetric X-ray response of n-i-p diodes deposited on PI. We measured the linearity of the photocurrent response to X-rays versus dose rate from which we have extracted the dosimetric X-ray sensitivity at various bias voltages. In particular, low bias voltage operation has been studied to assess the high energy efficiency of these kinds of sensors. A measurement of stability of X-ray response versus time has been shown. The effect of detectors annealing has been studied. Operation under bending at various bending radii is also shown.

The increasing use of complex and high dose-rate treatments in radiation therapy necessitates advanced detectors to provide accurate dosimetry. Rather than relying on pre-treatment quality assurance (QA) measurements alone, many countries are now mandating the use of in vivo dosimetry, whereby a dosimeter is placed on the surface of the patient during treatment. Ideally, in vivo detectors should be flexible to conform to a patient's irregular surfaces.This study aims to characterize a novel hydrogenated amorphous silicon (a-Si:H) radiation detector for the dosimetry of therapeutic x-ray beams. The detectors are flexible as they are fabricated directly on a flexible polyimide (Kapton) substrate.The potential of this technology for application as a real-time flexible detector is investigated through a combined dosimetric and flexibility study. Measurements of fundamental dosimetric quantities were obtained including output factor (OF), dose rate dependence (DPP), energy dependence, percentage depth dose (PDD), and angular dependence. The response of the a-Si:H detectors investigated in this study are benchmarked directly against commercially available ionization chambers and solid-state diodes currently employed for QA practices.The a-Si:H detectors exhibit remarkable dose linearities in the direct detection of kV and MV therapeutic x-rays, with calibrated sensitivities ranging from (0.580 ± 0.002) pC/cGy to (19.36 ± 0.10) pC/cGy as a function of detector thickness, area, and applied bias. Regarding dosimetry, the a-Si:H detectors accurately obtained OF measurements that parallel commercially available detector solutions. The PDD response closely matched the expected profile as predicted via Geant4 simulations, a PTW Farmer ionization chamber and a PTW ROOS chamber. The most significant variation in the PDD performance was 5.67%, observed at a depth of 3 mm for detectors operated unbiased. With an external bias, the discrepancy in PDD response from reference data was confined to ± 2.92% for all depths (surface to 250 mm) in water-equivalent plastic. Very little angular dependence is displayed between irradiations at angles of 0° and 180°, with the most significant variation being a 7.71% decrease in collected charge at a 110° relative angle of incidence. Energy dependence and dose per pulse dependence are also reported, with results in agreement with the literature. Most notably, the flexibility of a-Si:H detectors was quantified for sample bending up to a radius of curvature of 7.98 mm, where the recorded photosensitivity degraded by (-4.9 ± 0.6)% of the initial device response when flat. It is essential to mention that this small bending radius is unlikely during in vivo patient dosimetry. In a more realistic scenario, with a bending radius of 15-20 mm, the variation in detector response remained within ± 4%. After substantial bending, the detector's photosensitivity when returned to a flat condition was (99.1 ± 0.5)% of the original response.This work successfully characterizes a flexible detector based on thin-film a-Si:H deposited on a Kapton substrate for applications in therapeutic x-ray dosimetry. The detectors exhibit dosimetric performances that parallel commercially available dosimeters, while also demonstrating excellent flexibility results.

Abstract Hydrogenated amorphous silicon (a-Si:H) is a material with a very good radiation hardness and with the possibility of deposition on flexible substrates like Polyimide (PI). Exploiting these properties, the HASPIDE (Hydrogenated Amorphous Silicon PIxels DEtectors) project has the goal of developing a-Si:H detectors on flexible substrates for beam dosimetry and profile monitoring, neutron detection and space experiments. The detectors for this experiment will be developed in two different structures: the n-i-p diode structure, which has been used up to now for the construction of the planar a-Si:H detectors, and the recently developed charge selective contact structure. In the latter the doped layers (n or p) are replaced with charge selective materials namely electron-selective conductive metal-oxides (TiO 2 or Al:ZnO) and hole-selective conductive metal oxides (MoO x ). In this paper preliminary data on the capabilities of these detectors to measure X-ray and electron fluxes will be presented. In particular, the linearity, the sensitivity, the stability and dark current in various conditions will be discussed.

We designed, constructed and operated a cylindrical, scintillating fibres, tracker detector in order to measure the directional flux of cosmic ray muons underground. This instrument named Muon Ground Radiograph (MGR) was developed to study the fluctuation of the density in the soil that causes detection anisotropies in the arrival direction of cosmic ray muons observed in a tracker detector located underground. Density fluctuations may reveal hidden cavities or buried structures and can contribute to archaeological findings. The shape of the detector we used, for this purpose, is cylindrical, 14 cm diameter and 224 cm height, and it can be inserted into a 20 cm diameter hole in the ground at a maximum depth of 30 m. This paper will describe the instrument design and construction and also report some results of two observational campaigns in the town of Aquileia the Claudio and Traiano port.

Abstract We have measured the radiation tolerance of poly-crystalline and single-crystalline diamonds grown by the chemical vapor deposition (CVD) process by measuring the charge collected before and after irradiation in a 50 m pitch strip detector fabricated on each diamond sample. We irradiated one group of sensors with 800 MeV protons, and a second group of sensors with 24 GeV protons, in steps, to protons cm −2 and protons cm −2 respectively. We observe the sum of mean drift paths for electrons and holes for both poly-crystalline CVD diamond and single-crystalline CVD diamond decreases with irradiation fluence from its initial value according to a simple damage curve characterized by a damage constant for each irradiation energy and the irradiation fluence. We find for each irradiation energy the damage constant, for poly-crystalline CVD diamond to be the same within statistical errors as the damage constant for single-crystalline CVD diamond. We find the damage constant for diamond irradiated with 24 GeV protons to be and the damage constant for diamond irradiated with 800 MeV protons to be . Moreover, we observe the pulse height decreases with fluence for poly-crystalline CVD material and within statistical errors does not change with fluence for single-crystalline CVD material for both 24 GeV proton irradiation and 800 MeV proton irradiation. Finally, we have measured the uniformity of each sample as a function of fluence and observed that for poly-crystalline CVD diamond the samples become more uniform with fluence while for single-crystalline CVD diamond the uniformity does not change with fluence.

The silicon tracker of the AMS-02 detector measures the trajectory in three dimensions of electrons, protons and nuclei to high precision in a dipole magnetic field and thus measures their rigidity (momentum over charge) and the sign of their charge. In addition, it measures the specific energy loss of charged particles to determine the charge magnitude. Ladders from the AMS-02 tracker have been exposed to ion beams at CERN and GSI to study their response to nuclei from helium up to the iron group. The longest ladder, 72×496mm2, verified in the tests contains 12 sensors. Good charge resolution is observed up to iron.

We measured the radiation tolerance of commercially available diamonds grown by the Chemical Vapor Deposition process by measuring the charge created by a 120 GeV hadron beam in a 50 μm pitch strip detector fabricated on each diamond sample before and after irradiation. We irradiated one group of samples with 70 MeV protons, a second group of samples with fast reactor neutrons (defined as energy greater than 0.1 MeV), and a third group of samples with 200 MeV pions, in steps, to (8.8±0.9) × 1015 protons/cm2, (1.43±0.14) × 1016 neutrons/cm2, and (6.5±1.4) × 1014 pions/cm2, respectively. By observing the charge induced due to the separation of electron-hole pairs created by the passage of the hadron beam through each sample, on an event-by-event basis, as a function of irradiation fluence, we conclude all datasets can be described by a first-order damage equation and independently calculate the damage constant for 70 MeV protons, fast reactor neutrons, and 200 MeV pions. We find the damage constant for diamond irradiated with 70 MeV protons to be 1.62±0.07(stat)±0.16(syst)× 10-18 cm2/(p μm), the damage constant for diamond irradiated with fast reactor neutrons to be 2.65±0.13(stat)±0.18(syst)× 10-18 cm2/(n μm), and the damage constant for diamond irradiated with 200 MeV pions to be 2.0±0.2(stat)±0.5(syst)× 10-18 cm2/(π μm). The damage constants from this measurement were analyzed together with our previously published 24 GeV proton irradiation and 800 MeV proton irradiation damage constant data to derive the first comprehensive set of relative damage constants for Chemical Vapor Deposition diamond. We find 70 MeV protons are 2.60 ± 0.29 times more damaging than 24 GeV protons, fast reactor neutrons are 4.3 ± 0.4 times more damaging than 24 GeV protons, and 200 MeV pions are 3.2 ± 0.8 more damaging than 24 GeV protons. We also observe the measured data can be described by a universal damage curve for all proton, neutron, and pion irradiations we performed of Chemical Vapor Deposition diamond. Finally, we confirm the spatial uniformity of the collected charge increases with fluence for polycrystalline Chemical Vapor Deposition diamond, and this effect can also be described by a universal curve.

Abstract Hydrogenated Amorphous Silicon (a-Si:H) is a well known material for its intrinsic radiation hardness and is primarily utilized in solar cells as well as for particle detection and dosimetry. Planar p-i-n diode detectors are fabricated entirely by means of intrinsic and doped PECVD of a mixture of Silane (SiH 4 ) and molecular hydrogen. In order to develop 3D detector geometries using a-Si:H, two options for the junction fabrication have been considered: ion implantation and charge selective contacts through atomic layer deposition. In order to test the functionality of the charge selective contact electrodes, planar detectors have been fabricated utilizing this technique. In this paper, we provide a general overview of the 3D fabrication project followed by the results of leakage current measurements and X-ray dosimetric tests performed on planar diodes containing charge selective contacts to investigate the feasibility of the charge selective contact methodology for integration with the proposed 3D detector architectures.

Hydrogenated amorphous silicon (a-Si:H) particle detectors have been considered as alternatives to crystalline silicon detectors (c-Si) in high radiation environments, due to their excellent radiation hardness. However, although their capability for particle flux measurement in beam monitoring applications is quite satisfactory, their minimum ionizing particle (MIP) detection has always been problematic because of the poor signal-to-noise ratio caused by a low charge collection efficiency and relatively high (compared to crystalline silicon) leakage current. In this article, after a review of the status of technological research for a-Si:H detectors, a perspective view on MIP detection and beam flux measurements with these detectors will be given.

Abstract This report presents the results obtained with a prototype silicon-tungsten (Si-W) electromagnetic calorimeter, conceived as a fine-grained imaging device to carry out studies of the antimatter component in primary cosmic radiation. The calorimeter prototype contains 20 x , y sampling layers interleaved with 19 showering material planes. One sensitive layer is obtained with two silicon strip detectors (Si-D) (60 × 60) mm 2 , each divided into 16 strips, 3.6 mm wide; the two detectors are assembled back to back with perpendicular strips. This allows the transverse distributions of the shower in both coordinates at each sampling (0.5 X 0 ) to be pictured. The basic characteristics of the design and the experimental results obtained on a test beam at the CERN proton synchrotron (PS) for electrons and pions are reported. The main results presented are the response of the calorimeter to the electron at various energies (1–7 GeV), and the transverse shower profiles at different calorimeter depths as well as the patterns of the electromagnetic shower and those of the interacting and non-interacting pions. The capability of the calorimeter in measuring the direction of the incoming electromagnetic particle from the pattern of the shower has been evaluated at different energies. These results are encouraging in view of the possible use of this detector to search for high-energy γ sources in space.

A measurement of the negative muon flux in the atmosphere has been made using a superconducting magnet spectrometer during the ascent part of a balloon flight experiment performed on September 5, 1989 from Prince Albert, Saskatchewan (Canada). The negative muon component has been measured over the momentum range 0.3--40 GeV/c with an altitude increasing from 0.6 to 36 km above sea level. This is the first time that results from such wide intervals in momentum and atmospheric depth have been obtained using a single apparatus. The flux growth curve with atmospheric depth is momentum dependent; the low energy muon flux peaks around 150 g/${\mathrm{cm}}^{2}$ and higher energy muons penetrate to larger depths in the atmosphere. The flux decreases exponentially with increasing depth above 200 g/${\mathrm{cm}}^{2}$. The attenuation length ${\mathrm{\ensuremath{\Lambda}}}_{\mathit{e}}$ increases almost linearly with the muon momentum at a rate of about 90 (g/${\mathrm{cm}}^{2}$)/(GeV/c) in the 0.3--8 GeV/c range. The momentum spectra at different altitudes can be described by power laws, provided that the spectral index is left free to change with altitude. We found that an index value of -2.5\ifmmode\pm\else\textpm\fi{}0.2 can give a good description of the data for momenta between 2 and 40 GeV/c in the depth range 20--400 g/${\mathrm{cm}}^{2}$. Below 1 GeV/c, the spectrum gradually steepens as the atmospheric depth decreases. Above 600 g/${\mathrm{cm}}^{2}$ a peak around 0.5 GeV/c arises. \textcopyright{} 1995 The American Physical Society.

We have investigated the effects produced by exposing a field programmable gate array (FPGA) based on static RAM to an ion beam. Tested devices have been taken from FLEX10K family manufactured by Altera Corporation. These parts are commercial graded and not qualified for application in radioactive environments. A design based on mixed plain and triple-modular-redundant (TMR) shift registers (SR's) has been implemented in the FPGA under test. No single event upset (SEU) was detected in the shift registers. The predominant effect of irradiation with heavy ions was the single event functional interrupt (SEFI). SEFI's have been induced from SEU's in the configuration memory. No destructive latch-up has been observed. During irradiation, supply current has been observed to increase almost linearly with ion fluence, probably due to progressive SEU-induced driver contentions. The configuration memory cross section has been calculated and we have found the saturation level of 2.5/spl middot/10/sup -8/ cm/sup 2/ /bit reached with LET>40 MeV/spl middot/cm/sup 2//mg.

The Alpha Magnetic Spectrometer AMS-02 [1]-[4] is an astro particle physics experiment running on the International Space Station (ISS; see Figure 1) since May 19, 2011. Its missions include the search for antimatter and the identification of the nature of dark matter. The AMS silicon tracker is the only subdetector inside the AMS permanent magnet that can detect the charge of a moving particle to distinguish an anti-particle from particle (see Table 1 for nomenclature).

Diamond devices have now become ubiquitous in the LHC experiments, finding applications in beam background monitoring and luminosity measuring systems. This sensor material is now maturing to the point that the large pads in existing diamond detectors are being replaced by highly granular tracking devices, in both pixel and strip configurations, for detector systems that will be used in Run II at the LHC and beyond. The RD42 collaboration has continued to seek out additional diamond manufacturers and quantify the limits of the radiation tolerance of this material. The ATLAS experiment has recently installed, and is now commissioning a fully-fledged pixel tracking detector system based on diamond sensors. Finally, RD42 has recently demonstrated the viability of 3D biased diamond sensors that can be operated at very low voltages with full charge collection. These proceedings describe all of these advances.

There is currently a renewed interest in hydrogenated amorphous silicon (a-Si:H) for use in particle detection applications. Whilst this material has been comprehensively investigated from a numerical perspective within the context of photovoltaic and imaging applications, the majority of work related to its application in particle detection has been limited to experimental studies. In this study, a material model to mimic the electrical and charge collection behaviour of a-Si:H is developed using the SYNOPSYSc Technology Computer Aided Design (TCAD) simulation tool Sentaurus. The key focus of the model is concerned with the quasi-continuous defect distribution of acceptor and donor defects near the valence and conduction bands (tails states) and a Gaussian distribution of acceptor and donor defects within the mid-gap with the main parameters being the defect energy level, capture cross-section and trap density. Currently, Sentaurus TCAD offers Poole-Frenkel mobility and trap models, however, these were deemed to be incompatible with thick a-Si:H substrates. With the addition of a fitting function, the model was able to provide acceptable agreement (within 10nA.cm-2) between simulated and experimental leakage current density for a-Si:H substrates with thicknesses of 12 and 30μm. Additional transient simulations performed to mimic the response of the 12μm thick device demonstrated excellent agreement (1%) with experimental data found in the literature in terms of the operating voltage required to deplete thick a-Si:H devices. The a-Si:H model developed in this work provides a method of optimising a-Si:H based devices for particle detection applications.

Hydrogenated amorphous silicon (a-Si:H) can be produced by plasma-enhanced chemical vapor deposition (PECVD) of SiH4 (silane) mixed with hydrogen. The resulting material shows outstanding radiation hardness properties and can be deposited on a wide variety of substrates. Devices employing a-Si:H technologies have been used to detect many different kinds of radiation, namely, minimum ionizing particles (MIPs), X-rays, neutrons, and ions, as well as low-energy protons and alphas. However, the detection of MIPs using planar a-Si:H diodes has proven difficult due to their unsatisfactory S/N ratio arising from a combination of high leakage current, high capacitance, and limited charge collection efficiency (50% at best for a 30 µm planar diode). To overcome these limitations, the 3D-SiAm collaboration proposes employing a 3D detector geometry. The use of vertical electrodes allows for a small collection distance to be maintained while preserving a large detector thickness for charge generation. The depletion voltage in this configuration can be kept below 400 V with a consequent reduction in the leakage current. In this paper, following a detailed description of the fabrication process, the results of the tests performed on the planar p-i-n structures made with ion implantation of the dopants and with carrier selective contacts are illustrated.

Accurate measurements of under cutoff proton, electron, and positron fluxes in the energy range 0.07 ÷ 9.1 GeV have been performed with the Alpha Magnetic Spectrometer at altitudes of 370 ÷ 390 km in the geographic latitude interval ±51.7°. The flux maps as a function of the canonical adiabatic variables L , α o , and energy E are presented and discussed.

We will illustrate the design, assembly and test of an innovative, compact and low-cost cosmic-ray tracking detector developed at the INFN laboratories of Trieste and Perugia (Italy), which makes use of the most recent technologies for scintillating fibres and multianode photomultiplier tubes. The detector has been designed in particular for underground investigation: it lies inside a cylinder made of aluminium and can be lowered down a 20 cm diameter hole drilled into the ground, reaching a depth of 10–30 m. It measures the cosmic ground penetrating muon flux as a function of the direction to obtain information about the density of the material through which the cosmic rays travel before reaching the detector itself. The whole instrumentation (that is, the detector, a computer for data acquisition and a power supply), is simple to install and easy to handle. Examples of fields in which the instrument can be useful are geology, archaeology, spelaeology. In the last few months we tested the performance of the detector in two different Italian archaeological sites (Aquileia, UD and Fiumicino, RM). The acquired data are presented in this work.

Detectors based on Chemical Vapor Deposition (CVD) diamond have been used extensively and successfully in beam conditions/beam loss monitors as the innermost detectors in the highest radiation areas of Large Hadron Collider (LHC) experiments. The startup of the LHC in 2015 brought a new milestone where the first polycrystalline CVD (pCVD) diamond pixel modules were installed in an LHC experiment and successfully began operation. The RD42 collaboration at CERN is leading the effort to develop polycrystalline CVD diamond as a material for tracking detectors operating in extreme radiation environments. The status of the RD42 project with emphasis on recent beam test results is presented.

Abstract The next generation of high-energy physics experiments at future hadronic colliders will require tracking detectors able to efficiently operate in extreme radiation environments, where expected fluences will exceed 1 × 10 17 n eq /cm 2 . This new operating scenario imposes many efforts on the design of effective and radiation-resistant particle detectors. Low-Gain Avalanche Diode (LGAD) represents a remarkable advance because the radiation damage effects can be mitigated by exploiting its charge multiplication mechanism after heavy irradiation. To obtain the desired gain (about 10–20) on the sensor output signal, a careful implementation of the “multiplication” region is needed (i.e. the high-field junction implant). Moreover, a proper design of the peripheral region (namely, the guard-ring structure) is crucial to prevent premature breakdown and large leakage currents at very high fluences, when the bias voltage applied creates an electric field higher than 15 V/μm. In this contribution, the design of LGAD sensors for extreme fluence applications is discussed, addressing the critical technological aspects such as the choice of the active substrate thickness, the gain layer design and the optimization of the sensor periphery. The impact of several design strategies is evaluated with the aid of Technology-CAD (TCAD) simulations based on a recently proposed model for the numerical simulation of radiation damage effects on LGAD devices.

Hydrogenated amorphous silicon is a well-known detector material for its radiation resistance. For this reason it has been used in particle beam flux measurements and in solar panels designed for space applications. This study concern 10μm thickness, p-i-n and charge selective contacts planar diode detectors which were irradiated with neutrons to two fluence values: 1016 neq/cm2 and 5 × 1016 neq/cm2. In order to evaluate their radiation resistance, detector leakage current and response to x-ray photons have been measured. The effect of annealing for performance recovery at 100 °C for 12 and 24 h has also been studied. The results for the 1016 neq/cm2 irradiation show a factor 2 increase in leakage current that is completely recovered after annealing for p-i-n devices while charge selective contacts devices show an overall decrease of the leakage current at the end of the annealing process compared to the measurement before the irradiation. X-ray dosimetric sensitivity degrades, for this fluence, at the end of irradiation, but partially recovers for charge selective contact devices and increases for p-i-n devices at the end of the annealing process. Concerning the 5 × 1016 neq/cm2 irradiation test (for p-i-n structures only), due to the activation that occurred during the irradiation phase, the measurements were taken after 146 days of storage at around 0 °C, during this period, a self-annealing effect may have occurred. Therefore, the results after irradiation and storage show a noticeable degradation in leakage current and x-ray sensitivity with a small recovery after annealing.

Hydrogenated amorphous silicon (a-Si:H) is a well known material for its radiation resistance and for the possibility of deposition on flexible substrates like Polyimide (PI), polyethylene terephthalate (PET) or polyethylene naphthalate (PEN). Due to the properties of a-Si:H its usage for dosimetry, beam monitoring for particle physics and nuclear medicine, as well as, radiation flux measurement for space applications and neutron flux measurement can be foreseen. In this paper the dosimetric X-ray response of p-i-n diodes deposited on Polyimide will be studied. In particular we will study the linearity of the photocurrent response to X-rays versus dose-rate from which we will extract the dosimetric sensitivity at various bias voltages. We will repeat this study for devices having two different areas (2 mm x 2 mm and 5 mm x 5 mm) also a measurement of stability of X-ray response versus time will be shown.

Hydrogenated amorphous silicon (a-Si:H) is a material having an intrinsically high radiation hardness that can be deposited on flexible substrates like Polyimide. For these properties a-Si:H can be used for the production of flexible sensors. a-Si:H sensors can be successfully utilized in dosimetry, beam monitoring for particle physics (x-ray, electron, gamma-ray and proton detection) and radiotherapy, radiation flux measurement for space applications (study of solar energetic particles and stellar events) and neutron flux measurements. In this paper we have studied the dosimetric x-ray response of n-i-p diodes deposited on Polyimide. We measured the linearity of the photocurrent response to x-rays versus dose-rate from which we have extracted the dosimetric x-ray sensitivity at various bias voltages. In particular low bias voltage operation has been studied to assess the high energy efficiency of these kind of sensor. A measurement of stability of x-ray response versus time has been shown. The effect of detectors annealing has been studied. Operation under bending at various bending radii is also shown.

The Alpha Magnetic Spectrometer (AMS) is designed as an independent module for installation on the International Space Station (ISS) in the year 2003 for an operational period of three years. The principal scientific objectives include the searches for antimatter and dark matter in cosmic rays. The AMS tracker uses silicon microstrip sensors to reconstruct charged-particle trajectories. A first version of the AMS, equipped with 2.1 m2 of silicon sensors and a permanent magnet, was flown on the NASA space shuttle Discovery duringJune 2–12, 1998. In this contribution, we describe the detector and present results of the tracker performance duringthe flight.

Using a superconducting magnet spectrometer, we have measured the energy spectra of electrons, positrons, and protons at ground level at an atmospheric depth of 945 g/cm². The differential energy spectrum of the electron component has been determined in the momentum interval between 0.1 and 2.0 GeV/ c . This spectrum can be described by two power laws, one below 600 MeV with a spectral index of −1.8±0.1 and the other above this energy with an index of −2.9±0.2. The absolute flux values measured here are not in agreement with the earlier results. The fraction of positrons varies from a value of 0.45 at 200 MeV to about 0.5 above 1 GeV, which is consistent with the theoretical expectation. The momentum dependence of the e /µ ratio in the region between 0.25 and 2.0 GeV/ c is proportional to p −2.2 , and it appears that the soft component of the ionizing radiation might dominate at ground level at kinetic energies below about 70 MeV. The proton energy spectrum has been determined as a power law in kinetic energy between 2.9 and 19.1 GeV with a spectral index of −2.66±0.26. The p /µ ratio obtained from this experiment seems to have a steeper momentum dependence than from previous experiments.

In sight of the luminosity increase of the High Luminosity-LHC (HL-LHC), most experiments at the CERN Large Hadron Collider (LHC) are planning upgrades for their innermost layers in the next 5–10 years. These upgrades will require more radiation tolerant technologies than exist today. Usage of Chemical Vapor Deposition (CVD) diamond as detector material is one of the potentially interesting technologies for the upgrade. CVD diamond has been used extensively in the beam condition monitors of BaBar, Belle, CDF and all LHC experiments. Measurements of the radiation tolerance of the highest quality polycrystalline CVD material for a range of proton energies, pions and neutrons obtained with this material are presented. In addition, new results on the evolution of various semiconductor parameters as a function of the dose rate are described.

Accurate measurements of electron and positron fluxes in the energy range 0.2–10 GeV have been performed with the Alpha Magnetic Spectrometer (AMS) at altitudes of 320–390 km in the geographic latitude interval ±51.7°. We focus on the fluxes measured in the regions nearby the South Atlantic Anomaly, defined by the local magnetic values of the magnetic field B (0.21 ≤ B ≤ 0.26 G) at the altitude of AMS. A clear transition from the Stably Trapped population typical of the Inner Van Allen belts to Quasi‐Trapped population in the regions underneath the Van Allen belts is observed. The high energy observations demonstrate the relatively higher abundance of positrons in the Inner Van Allen belts, for both the Stably Trapped and the Quasi‐Trapped populations. The flux maps as a function of the canonical adiabatic variables L, α o are presented for the interval 0.95 < L < 3, 0° < α o < 90° for electron energies below 10 GeV and positrons energies below 3 GeV. The results are compared with existing data at lower energies.

By using an experimental setup based on thin and thick double-sided microstrip silicon detectors, it has been possible to identify the fragmentation products due to the interaction of very high energy primary ions on different targets. Here we report total and partial cross-sections measured at GSI (Gesellschaft fur Schwerionenforschung), Darmstadt, for 500 MeV/n energy <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$^{12}C$</tex></formula> beam incident on water (in flasks), polyethylene, lucite, silicon carbide, graphite, aluminium, copper, iron, tin, tantalum and lead targets. The results are compared to the predictions of GEANT4 (v4.9.4) and FLUKA (v11.2) Monte Carlo simulation programs.

In the present study, results towards the development of a 3D diamond sensor are presented. Conductive channels are produced inside the sensor bulk using a femtosecond laser. This electrode geometry allows full charge collection even for low quality diamond sensors. Results from testbeam show that charge is collected by these electrodes. In order to understand the channel growth parameters, with the goal of producing low resistivity channels, the conductive channels produced with a different laser setup are evaluated by Raman spectroscopy.

The silicon sampling calorimeter presented is conceived as a fine grained imaging device to carry out studies of the anti-matter component in the primary cosmic radiation; it will be used in balloon payload program starting in 1993.The first sampling layer (48x48 cm 2) of this silicon calorimeter has been completed and successfully tested.We report the first results form studies performed at the CERN PS t7 beam.The complete calorimeter contains 20 xy sampling layers (strip pitch 3.6 ram) interleaved with 19 showering material planes (tungsten 0.5 X0).This allows to picture the transverse distributions of the shower in both coordinates at each sampling.The outstanding imaging capabilities reflects in high particle identification power.Preliminary results from beam tests performed with antiprotons at 3.5 GeV on a tower prototype of the calorimeter are reported.

Accurate measurements of under cutoff proton fluxes in the energy range 0.07–9.1 GeV have been performed with the Alpha Magnetic Spectrometer (AMS) at altitudes of 370–390 km in the geographic latitude interval ±51.7°. A clear transition from a Stably Trapped population typical of the Inner Van Allen belts, in the region of the South Atlantic Anomaly (SAA), to a Quasi‐Trapped population in the regions underneath the Van Allen belts outside the SAA is observed. The flux maps as a function of the canonical adiabatic variables L, α o , and energy E are presented and discussed.

We have measured the radiation tolerance of commercially available diamonds grown by the Chemical Vapor Deposition process by measuring the charge created by a 120 GeV hadron beam in a 50 µm pitch strip detector fabricated on each diamond sample before and after irradiation.We irradiated one group of samples with 70 MeV protons, a second group of samples with fast reactor neutrons (defined as energy greater than 0.1 MeV) and a third group of samples with 200 MeV pions, in steps, to (8.8 ± 0.9) × 10 15 protons/cm 2 , (1.43 ± 0.14) × 10 16 neutrons/cm 2 and (6.5 ± 0.5) × 10 14 pions/cm 2 respectively.By observing the charge induced due to the separation of electron-hole pairs created by the passage of the hadron beam through each sample, on an event-by-event basis, as a function of irradiation fluence, we conclude all data sets can be described by a first order damage equation and independently calculate the damage constant for 70 MeV protons, fast reactor neutrons and 200 MeV pions.We find the damage constant for diamond irradiated with 70 MeV protons to be 1.61 ± 0.07 (stat) ± 0.15 (syst) × 10 -18 cm 2 /(p µm), the damage constant for diamond irradiated with fast reactor neutrons to be 2.65 ± 0.13 (stat) ± 0.16 (syst) × 10 -18 cm 2 /(n µm) and the damage constant for diamond irradiated with 200 MeV pions to be 2.0 ± 0.2 (stat) ± 0.5 (syst) × 10 -18 cm 2 /(π µm).The damage constants from this measurement were analyzed together with our previously published 24 GeV proton irradiation and 800 MeV proton irradiation damage constant data to derive the first comprehensive set of relative damage constants for Chemical Vapor Deposition diamond.We find 70 MeV protons are 2.60 ± 0.27 times more damaging than 24 GeV protons, fast reactor neutrons are 4.27 ± 0.34 times more damaging than 24 GeV protons and 200 MeV pions are 3.2 ± 0.8 more damaging than 24 GeV protons.We also observe the measured data can be described by a universal damage curve for all proton, neutron and pion irradiations we have performed of Chemical Vapor Deposition diamond.Finally, we confirm the FWHM/MP ratio of the signal spectrum, a measure of the spatial uniformity of the collected charge, decreases with fluence for polycrystalline Chemical Vapor Deposition diamond and this effect can also be described by a universal curve.

Abstract The vertex detectors for the future hadronic colliders will operate under proton fluencies above 10 16 p/cm 2 . Crystalline Silicon detector technology, up to now, has kept the pace of the increasing fluencies in the LHC era and it is still the prevalent vertex detector material for the present and for the immediate future. Looking ahead in time, an alternative solution for such a detector has to be found because for the future there is no guarantee that Crystalline Silicon will hold this challenge. For this reason the development of hydrogenated amorphous silicon vertex detectors based on 3D-technology have been proposed and the technological solutions in order to build these detectors are described in this paper.

Commercial off-the-shelf components have been tested for their use on the power supplies of the AMS and PAMELA experiments. The test has been performed using the CALLIOPE Co60 source at the Casaccia (Rome-Italy) Laboratory of ENEA according to the ESA/SCC 22900 specifications. The total dose for this test was 30 krads. Measurements of relevant parameters for each component has been taken at 3, 10 and 30 krads. Annealing and ageing has also been performed according to the ESA specification. The results on the degradation of performances in discrete transistors, Op-Amps, regulators and other analog and digital components are reported.

A pulsed nanosecond IR laser diode system to automatically test the Single Event Effects in laboratory is described.The results of Single Event Latchup (SEL) test on two VLSI chips (VA HDR64, 0.8 and 1:2 mm technology) are discussed and compared to those obtained with high-energy heavy ions at GSI (Darmstadt).

Commercial off-the-shelf components can be succesfully used in scientific payloads installed in spacecraft flying on Low Earth Orbits (LEO). Several experiments (AMS01, NINA) have already used these components, some others are planning to use them (AMS02, PAMELA and GLAST). In order to establish the reliability of these components careful tests need to be performed according to space qualification rules. There are two main types of possible damage that needs to be tested: the total dose damage and the single event effects (SEE). In this paper we will describe the physical cause of both the effects, explain how to conduct a test according to ESA/SSC standard rules and give some examples of components that have been tested by the AMS collaboration.

Recently, a polycrystalline chemical vapor deposited (pCVD) 3D diamond detector with graphitic in bulk electrodes, fabricated using a pulsed laser technique has been evaluated for photon beam radiation dosimetry during in-air exposure. The same 3D diamond detector, has now been investigated to evaluate its performance under clinically relevant conditions putting the detector inside a Polymethylmethacrylate (PMMA) phantom, to obtain higher precision dosimetric measurements. The detector leakage current was of the order of ± 25 pA or less for bias voltages up to −100 V. The 3D detector was tested for time stability and repeatability showing excellent performance with less than 0.6% signal variation. It also showed a linear response for low dose rates with a deviation from linearity of 2%. It was also possible to verify the detector response as a function of the depth in PMMA up to 18 cm.

DSPs from Analog Device (ADSP2187 and ADSP2189) have been tested for Single Event Effects (SEE) in order to be used in a Space Station Particle Physics experiment. We tested these devices at GSI (Darmstadt, Germany) with high energy (100 to 800 MeV/nucleon) xenon, gold and uranium ions. We also tested laser induced latchup on ADSP2187L. The results on cross section are compared with those obtained during the beam test.

The RD53 collaboration is developing a large scale pixel front-end chip, which will be a tool to evaluate the performance of 65 nm CMOS technology in view of its application to the readout of the innermost detector layers of ATLAS and CMS at the HL-LHC. Experimental results of the characterization of small prototypes will be discussed in the frame of the design work that is currently leading to the development of the large scale demonstrator chip RD53A to be submitted in early 2017. The paper is focused on the analog processors developed in the framework of the RD53 collaboration, including three time over threshold front-ends, designed by INFN Torino and Pavia, University of Bergamo and LBNL and a zero dead time front-end based on flash ADC designed by a joint collaboration between the Fermilab and INFN. The paper will also discuss the radiation tolerance features of the front-end channels, which were exposed to up to 800 Mrad of total ionizing dose to reproduce the system operation in the actual experiment.

RD53A is a large scale 65 nm CMOS pixel demonstrator chip that has been developed by the RD53 collaboration for very high rate (3 GHz/cm 2 ) and very high radiation levels (500 Mrad, possibly 1 Grad) for ATLAS and CMS phase 2 upgrades.It features serial powering operation and design variations in the analog and digital pixel matrix for different testing purposes.The design and verification of RD53A are described together with an outline of the plans to develop final pixel chips for the two experiments.

Hydrogenated amorphous silicon (a-Si:H) has remarkable radiation resistance properties and can be deposited on a lot of different substrates. A-Si:H based particle detectors have been built since mid 1980s as planar p-i-n or Schottky diode structures; the thickness of these detectors ranged from 1 to 50 micron. However MIP detection using planar structures has always been problematic due to the poor S/N ratio related to the high leakage current at high depletion voltage and the low charge collection efficiency. The usage of 3D detector architecture can be beneficial for the possibility to reduce inter-electrode distance and increase the thickness of the detector for larger charge generation compared to planar structures. Such a detector can be used for future hadron colliders for its radiation resistance and also for X-ray imaging. Furthermore the possibility of a-Si:H deposition on flexible materials (like kapton) can be exploited to build flexible and thin beam flux measurement detectors and x-ray dosimeters.

&lt;p&gt;Hydrogenated amorphous silicon is a well known detector material for its radiation resistance. This study concern 10 µm thickness, p-i-n and charge selective contacts planar diode detectors which were irradiated with neutrons at two fluence values: 1016 neq/cm2 and 5 x 1016 neq/cm2. In order to evaluate their radiation resistance, detector leakage current and response to X-ray photons have been measured. The effect of annealing for performance recovery at 100°C for 12 and 24 hours has also been studied. The results for the 1016 neq/cm2 irradiation show a factor 2 increase in leakage current that is completely recovered after annealing for p-i-n devices while charge selective contacts devices show an overall decrease of the leakage current at the end of the annealing process compared to the measurement before the irradiation. X-ray dosimetric sensitivity degrades, for this fluence, at the end of irradiation but partially recovers for charge selective contacts devices and increases for p-i-n devices at the end of the annealing process. Concerning the 5 x 1016 neq/cm2 irradiation test (for p-i-n structures only), due to the activation that occurred during the irradiation phase, the results were taken after 146 days of storage at around 0° C, during this period, a self-annealing effect may have occurred. Therefore the results after annealing show a small but noticeable degradation in leakage current and x-ray sensitivity, after irradiation and storage. &lt;/p&gt;

In this paper, by means of high-resolution photoemission, soft X-ray absorption and atomic force microscopy, we investigate, for the first time, the mechanisms of damaging, induced by neutron source, and recovering (after annealing) of p-i-n detector devices based on hydrogenated amorphous silicon (a-Si:H). This investigation will be performed by mean of high-resolution photoemission, soft X-Ray absorption and atomic force microscopy. Due to dangling bonds, the amorphous silicon is a highly defective material. However, by hydrogenation it is possible to reduce the density of the defect by several orders of magnitude, using hydrogenation and this will allow its usage in radiation detector devices. The investigation of the damage induced by exposure to high energy irradiation and its microscopic origin is fundamental since the amount of defects determine the electronic properties of the a-Si:H. The comparison of the spectroscopic results on bare and irradiated samples shows an increased degree of disorder and a strong reduction of the Si-H bonds after irradiation. After annealing we observe a partial recovering of the Si-H bonds, reducing the disorder in the Si (possibly due to the lowering of the radiation-induced dangling bonds). Moreover, effects in the uppermost coating are also observed by spectroscopies.

Diamond is used as detector material in high energy physics experiments due to its inherent radiation tolerance. The RD42 collaboration has measured the radiation tolerance of chemical vapour deposition (CVD) diamond against proton, pion, and neutron irradiation. Results of this study are summarized in this article. The radiation tolerance of diamond detectors can be further enhanced by using a 3D electrode geometry. We present preliminary results of a poly-crystalline CVD (pCVD) diamond detector with a 3D electrode geometry after irradiation and compare to planar devices of roughly the same thickness.

The WiZard Collaboration is engaged in a program to study the antimatter components of the cosmic rays. A silicon-tungsten (WiW) imaging calorimeter has been developed as part of this program. We present its performance and preliminary results, obtained during a balloon flight on September 8, 1993. The flight was dedicated to the measurement of the positron spectrum in the energy range 4–50 GeV and took place from Ft. Sumner, New Mexico.

High-precision tracking and charge selection with silicon strip detectors for relativistic ions has been investigated using a 12C beam of 1.5GeV/u at GSI with prototype modules developed for the AMS tracker. The ionization energy loss is measured and compared to the Landau–Vavilov theory for ions of charge number up to Z=6. The linearity in Z2 is examined. The capability to distinguish different Z values based on the ionization energy loss is evaluated. The spatial resolution of the silicon strip detectors is investigated for carbon ions. The angular distribution of multiple Coulomb scattering is studied with lead absorbers. The results are compared to the Molière theory and the Gaussian approximation of GEANT calculations.

In this work we present the results of full Geant4 and FLUKA simulations and comparison with dosimetry data of an electron LINAC of St. Maria Hospital located in Terni, Italy. The facility is being used primarily for radiotherapy and the goal of present study is the detailed investigation of electron beam parameters to evaluate the possibility to use the e-LINAC (during time slots when it is not used for radiotherapy) to test the performance of detector systems in particular those designed to operate in space. The critical beam parameters are electron energy, profile and flux available at the surface of device to be tested. The present work aims to extract these parameters from dosimetry calibration data available at the e-LINAC. The electron energy ranges is from 4 MeV to 20 MeV. The dose measurements have been performed by using an Advanced Markus Chamber which has a small sensitive volume.

In this work we present the results of full Geant4 and FLUKA simulations and comparison with dosimetry data of an electron LINAC of St. Maria Hospital located in Terni, Italy. The facility is being used primarily for radiotherapy and the goal of present study is the detailed investigation of electron beam parameters to evaluate the possibility to use e-LINAC (during time slots when it is not used for radiotherapy) to test the performance of detector systems in particular those designed to operate in space. The critical beam parameters are electron energy, profile and flux available at the surface of device to be tested. The present work aims to extract these parameters from dosimetry calibration data available at e-LINAC. The electron energy range is from 4 MeV to 20 MeV. The dose measurements have been performed by using an Advanced Markus Chamber which has a small sensitive volume.

This work discusses the design and the main results relevant to the characterization of analog front-end processors in view of their operation in the pixel detector readout chips of ATLAS and CMS at the High-Luminosity LHC.The front-end channels presented in this paper are part of RD53A, a large scale demonstrator designed in a 65 nm CMOS technology by the RD53 collaboration.The collaboration is now developing the full-sized readout chips for the actual experiments.Some details on the improvements implemented in the analog front-ends are provided in the paper.

Abstract We have constructed a silicon detector time-of-flight spectrometer operating at low temperature with an overall time resolution of 115.2 ± 2.0 ps at −50°C for minimum ionizing particles with unitary charge. We report the measurement of the overall time resolution of the telescope versus temperature in several relevant experimental conditions from −50 to 20°C. An extensive experimental study of the noise components of the detector and of the electronic readout as a function of the temperature is also given. We present an analysis of the measured noise components in order to account for the improvement of time resolution when the temperature varies from 20 to −50°C. Future developments of cold silicon strip detectors for time-of-flight determination are considered.

Among the several existent proposals for the cosmic antimatter search, the Wi#x005A-0304;ard project for the U.S. Space Station Freedom shows the greatest interest. A possible upgrading of the Wi#x005A-0304;ard apparatus, called Wi#x005A-0304;ard 2, is presented in order to sensibly improve the capability of detecting antihelium nuclei in the cosmic radiation.

The characteristics of a hydrogenated amorphous silicon (a-Si:H) detector are presented here for monitoring in space solar flares and the evolution of large energetic proton events up to hundreds of MeV. The a-Si:H presents an excellent radiation hardness and finds application in harsh radiation environments for medical purposes, for particle beam characterization and in space weather science and applications. The critical flux detection threshold for solar X rays, soft gamma rays, electrons and protons is discussed in detail.

Abstract The characteristics of a hydrogenated amorphous silicon (a-Si:H) detector are presented here for monitoring in space solar flares and the evolution of large energetic proton events up to hundreds of MeV. The a-Si:H presents an excellent radiation hardness and finds application in harsh radiation environments for medical purposes, for particle beam characterization and in space weather science and applications. The critical flux detection threshold for solar X rays, soft gamma rays, electrons and protons is discussed in detail.

The increase in luminosity and pileup foreseen for future colliders has recently pushed central pixel detector technology towards an increase in timing resolution. Increased time resolution can ease track reconstruction by adding a more precise timestamp to events for better track separation. An alternative approach to timing with silicon pixel detectors is proposed in this paper. Current approaches are based either on amplitude increase due to avalanche charge multiplication or in the reduction of charge collection time in a 3D geometry detector. Both approaches uses charge integration amplifiers for signal pre-amplification. The main feature of the proposed approach is based on current preamplifier signal readout and a more comprehensive approach to time resolution improvement. An additional aspect of this approach is that it shifts the attention from the detector design to the readout electronics design. The current pulse of a silicon detector has an intrinsically fast (in the order of 5 ps) rise-time however the actual rise-time of a detector connected to a current (low impedance) preamplifier is limited by the RC product of the input resistance and the capacitance of the detector/preamplifier interface and the bandwidth of the preamplifier itself; using low impedance amplifier and low capacitance pixel detector the rise-time of this pulse can be kept below 200 ps. The amplitude of the signal can be increased by bias overvoltage and temperature reduction (increases mobility shrinking the current pulse duration). Furthermore low temperature operation (- 30 °C or less) and the low input capacitance of the detector can help to reduce noise. The combination of reduced rise-time, increased amplitude and reduced noise can tentatively improve the overall time resolution below 20 ps which is considered the best result achieved.

A fast preamplifier for time-of-flight measurements has been constructed and operated at low temperature (−55°C). The design criteria and performance tests are presented. The measured rise time with a silicon strip detector with a capacitance of 15 pF is 3.2 ns. This preamplifier is employed in a cold silicon strip time-of-flight apparatus which has a time resolution of 120±6 ps at −55°C for minimum ionizing particles of unitary charge.

This paper describes the beam flux monitoring system that has been developed at the Superconducting Cyclotron at INFN-LNS (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Catania, Italy) in order to monitor the beam parameters such as energy, flux, beam profile, for SEE (Single Event Effects) cross-sections determination and DD (Displacement Damage) studies. In order to have an accurate and continuous monitoring of beam parameters we have developed fully automatic dosimetry setup to be used during SEE (with heavy ions) and DD (with protons up to 60 MeV) tests of electronic devices and systems. The final goal of our activity is to demonstrate that the operation of such a system in air is not detrimental to the accuracy on controlling the beam profile, energy and fluence delivered onto the DUT (Device Under Test) surface, even with non relativistic heavy ions. We have tested our beam monitoring system with the “Reference SEU monitor” developed by ESA/ESTEC, the results are discussed here.

The planned upgrade of the LHC to the High-Luminosity-LHC will push the luminosity limits above the original design values. Since the current detectors will not be able to cope with this environment ATLAS and CMS are doing research to find more radiation tolerant technologies for their innermost tracking layers. Chemical Vapour Deposition (CVD) diamond is an excellent candidate for this purpose. Detectors out of this material are already established in the highest irradiation regimes for the beam condition monitors at LHC. The RD42 collaboration is leading an effort to use CVD diamonds also as sensor material for the future tracking detectors. The signal behaviour of highly irradiated diamonds is presented as well as the recent study of the signal dependence on incident particle flux. There is also a recent development towards 3D detectors and especially 3D detectors with a pixel readout based on diamond sensors.

Leakage current and capacity dependence on temperature have been measured in the range − 30°C < t < 20°C for several silicon strip detectors. The experimental setup is composed of a copper test box enclosing 16 current-to-voltage converters and a refrigerator to set and control the required temperatures. These measurements were performed for noise minimization for the space calorimeter of the WiZard experiment to be operated on the American space station Freedom. The results show that the overall noise of the electronic readout chain may be significantly reduced by operating the calorimeter at low temperature.

This paper reports observations of the absolute momentum differential fluxes of negative pions and muons between 4 and 15 GeV/c and between 0.3 and 15 GeV/c, respectively, at an atmospheric depth of 5 g . The data have been collected by the balloon-borne experiment MASS (matter - antimatter space spectrometer) launched from Prince Albert (Canada) where the geomagnetic cut-off is 650 MV/c. The instrument was flown on the 5th of September 1989, the duration of the flight was 5.5 hours at an altitude of more than 117 000 ft. The measured fluxes are compared to calculations. The muon spectrum follows a power law in momentum with a spectral index of 2.36 above 2 GeV/c.

The Phase 2 upgrades of silicon pixel detectors at HL-LHC experiments feature extreme require- ments, such as: 50x50 μm pixels, high rate (3 GHz/cm2), unprecedented radiation levels (1 Grad), high readout speed and serial powering. As a consequence a new readout chip is required. In this framework the RD53 collaboration submitted RD53A, a large scale chip demonstrator de- signed in 65 nm CMOS technology, integrating a matrix of 400×192 pixels. It features design variations in the analog and digital pixel matrix for testing purposes. An overview of the building blocks will be given together with test results on single chips.

The RD53A large scale pixel demonstrator chip has been developed in 65 nm CMOS technology by the RD53 collaboration, in order to face the unprecedented design requirements of the pixel 2 phase upgrades of the CMS and ATLAS experiments at CERN. This prototype chip is designed to demonstrate that a set of challenging specifications can be met, such as: high granularity (small pixels of 50×50 or 25× 100 μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) and large pixel chip size (~2×2 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ), high hit rate (3 GHz/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ), high readout speed, very high radiation levels (500 Mrad - 1 Grad) and operation with serial powering. Furthermore, coping with the long latency of the trigger signal (~12.5 μs), used to select only events of interest in order to achieve sustainable output data rates, requires increased buffering resources in the limited pixel area. The RD53A chip has been fabricated in an engineer run. It integrates a matrix of 400×192 pixels and features various design variations in the analog and digital pixel matrix for testing purposes. This paper presents an overview of the chip architecture and of the methodologies used for efficient design of large complex mixed signal chips for harsh radiation environments. Experimental results obtained from the characterization of the RD53A chip are reported to demonstrate that design objectives have been achieved. Moreover, design improvements and new features being developed in the RD53B framework for final ATLAS and CMS production chips are discussed.

Cosmic antimatter search needs transportation systems of the apparatus outside the atmosphere. The Astromag facility on the NASA space station will be a great opportunity for such a search in the next future. Here we discuss the advantages achievable from silicon-detector technology in space research and we propose a silicon calorimeter as an ideal option to work in connection with the Astromag facility itself.

AMS-02 is a space experiment that will perform cosmic ray observations on board of the International Space Station starting from July 2009. This presentation describes the control electronics for the silicon tracker cooling system in the AMS-02 apparatus. It also contains a brief description of the tracker detector and its cooling system necessary for the description of the electronics. The tracker cooling system includes a set of various sensors and actuators which are necessary for bringing the tracker detector to a uniform temperature at which it can operate correctly. The sensors include: Pt1000 thermistors, semiconductor thermal sensors, differential and absolute pressure sensors, and pump rotational speed sensors. The actuators are: resistive heaters, peltier heat pumps, and liquid pumps. The electronics process the sensor signals, control the actuators, and perform automatic safeguard actions so that the system is capable of operating in a stand-alone mode, i.e. without operator intervention. The electronic system also sends relevant operational data to ground. This paper will describe the design, construction and space qualification of these control electronics.

&lt;p&gt;Hydrogenated amorphous silicon is a well known detector material for its radiation resistance. This study concern 10 µm thickness, p-i-n and charge selective contacts planar diode detectors which were irradiated with neutrons at two fluence values: 1016 neq/cm2 and 5 x 1016 neq/cm2. In order to evaluate their radiation resistance, detector leakage current and response to X-ray photons have been measured. The effect of annealing for performance recovery at 100°C for 12 and 24 hours has also been studied. The results for the 1016 neq/cm2 irradiation show a factor 2 increase in leakage current that is completely recovered after annealing for p-i-n devices while charge selective contacts devices show an overall decrease of the leakage current at the end of the annealing process compared to the measurement before the irradiation. X-ray dosimetric sensitivity degrades, for this fluence, at the end of irradiation but partially recovers for charge selective contacts devices and increases for p-i-n devices at the end of the annealing process. Concerning the 5 x 1016 neq/cm2 irradiation test (for p-i-n structures only), due to the activation that occurred during the irradiation phase, the results were taken after 146 days of storage at around 0° C, during this period, a self-annealing effect may have occurred. Therefore the results after annealing show a small but noticeable degradation in leakage current and x-ray sensitivity, after irradiation and storage. &lt;/p&gt;

Abstract A cold silicon strip telescope for time-of-flight determination at −55°C has been tested using a hadron beam at Saturne II. Saclay. We present performance tests of the telescope, the time-of-flight distributions between pairs of silicon hodoscopes and their dependence on temperature. A detailed description of the apparatus, the refrigerator system and the calibration procedures is also reported. A linear relationships between the time resolution and the temperature of the apparatus is measured. An improvement of a factor 2 in the time-of-flight resolution is observed when the temperature decreases from +20°C to −55°C

This paper describes the architecture, the performance and the qualification tests of the tracker detector power supply system for the AMS-02 experiment. The AMS-02 experiment will measure the cosmic ray spectrum from 0.5 GeV up to several TeV in space, looking for anti-matter, dark matter and strange quark matter. The experimental apparatus will be installed in the International Space Station (ISS) in year 2008. A preliminary version of this experiment has flown in 1998 on the STS-91 shuttle flight. The power supply system of the tracker has been designed optimizing noise performances, modularity and efficiency. Power is generated starting from a 28 V line coming from the power distribution box for the entire experiment. This power is converted into the needed voltages by means of DC-DC converters, and for bias supply and front-end voltages is postregulated by means of linear regulators. Components off the shelf (COTS) have been extensively used in the construction of this power supply, however various radiation test campaigns have been performed in order to verify the reliability of these components. Active components were tested for total dose radiation damage and digital components were also tested for single event effects. The power supply architecture developed for the tracker detector has been used as a guideline for the development of the power supplies for the other detectors in the experiment.

Abstract This article describes the control electronics for the silicon tracker cooling system in the AMS-02 apparatus. It also contains a brief description of the cooling system itself necessary for the description of the electronics. The tracker cooling system includes a set of various sensors and actuators which are necessary for bringing the tracker detector to a uniform temperature at which it can operate correctly. In order to test the system performing the various qualification activities we have built also an Electronic Ground support equipment (EGSE). The EGSE should simulate the behaviour of all sensors and actuators previously mentioned.

This paper describes a study of background estimation in Modular x and gamma-ray Sensor (MXGS) on-board ESA's Atmosphere-Space Interactions Monitor (ASIM) mission, using Geant4 simulations and SPENVIS packages for particle flux generations.

The AMS-02 Tracker power supply system, described in this paper, has been designed optimizing noise performances, modularity and efficiency. The power is distributed starting from a 28V line coming from the power distribution system is converted into the needed voltages by means of DC-DC converters, and for bias supply and front-end voltages is post-regulated by means of linear regulators. Components Off The Shelf (COTS) have been extensively used in the construction of this power supply, however various radiation test campaigns have been performed in order to verify the reliability of these components. The power supply architecture developed for the tracker detector has been used as a guideline for the development of the power supplies for the other detectors in the experiment.

At present most experiments at the CERN Large Hadron Collider (LHC) are planning upgrades in the next 5-10 years for their innermost tracking layers as well as luminosity monitors to be able to take data as the luminosity increases and CERN moves toward the High Luminosity-LHC (HL-LHC). These upgrades will most likely require more radiation tolerant technologies than exist today. As a result this is one area of intense research, and Chemical Vapour Deposition (CVD) diamond is one such technology. CVD diamond has been used extensively in beam condition monitors as the innermost detectors in the highest radiation areas of all LHC experiments. This talk describes the preliminary radiation tolerance measurements of the highest quality polycrystalline CVD material for a range of proton energies and neutrons obtained with this material with the goal of elucidating the issues that should be addressed for future diamond based detectors. The talk presents the evolution of various semiconductor parameters as a function of dose.

A tracking calorimeter made of 3200 brass streamer tubes together with 3200 pick-up strips has been built to complement a magnetic spectrometer in order to detect cosmic antiprotons in space. The characteristics of such a calorimeter, the results of a preliminary test of a prototype as well as the properties of the whole apparatus are presented. The apparatus, designed to operate on a balloon at an altitude of about 40 km, can be considered as a second generation detector, capable in principle to solve the problem of the presence of low energy (≤1 Ge V/c) antiprotons in the cosmic rays which is still open because of the disagreement between the existent experimental data.

The conceptual design of the spectrometer and the scientific goals of the AMS experiment, are presented here as well as the measured performances for minimum ionising particles using ground level cosmic-rays and reconstructed events from space. The first results of a test done with relativistic carbon ions at GSI (Darmstadt) are also given, A preliminary version of the AMS apparatus flew on June 1998 on shuttle mission STS-91. In 2002 the complete system will be installed on the space station Alpha and it will take data for three years.

This paper describes the Monte Carlo program used for the simulation of antiproton interactions at intermediate energy inside a brass streamer-tube tracking calorimeter, to be used in a search for antimatter in cosmic rays, in the high atmosphere. The calorimeter is sensitive in the kinetic-energy range (100 ⧀v 5000) MeV and the Monte Carlo is tuned in this energy interval both for proton and antiproton interactions. The detector geometry, which consists of a set of plane slabs, may be easily extended to other calorimeter structures.

Siliconp +/n/n + detectors with medium resistivities (400–500 cm) have been analyzed as a function of neutron irradiation in the fluence range from 6.4·1011 n/cm2 to 2.5·1015 n/cm2. The changes in the effective carrier concentration have been related to the removal of the shallowlevel concentration induced by irradiation and to the introduction with the fluence of deep levels. The shallow levels have been studied by Thermally Stimulated Current (TSC) in the low-temperature range (10–20 K): a removal of one order of magnitude of the phosphorus concentration has been observed for fluences of the order of 1 · 1014 n/cm2. The presence of deep levels has been investigated by TSC and current-DLTS techniques.

This paper describes the architecture, the performance and the qualification tests of the Tracker detector power supply system for the AMS-02 experiment. The AMS-02 experiment will measure the cosmic ray spectrum from 0.5 GeV up to several TeV in space, looking for anti-matter, dark matter and strange quark matter. The experimental apparatus will be installed in the International Space Station (ISS) in year 2008. A preliminary version of this experiment has flown in 1998 on the STS-91 shuttle flight. The power supply system of the tracker has been designed optimizing noise performances, modularity and efficiency. Power is generated starting from a 28 V line coming from the power distribution box for the entire experiment. This power is converted into the needed voltages by means of DC-DC converters, and for bias supply and front-end voltages is postregulated by means of linear regulators. Components Off The Shelf (COTS) have been extensively used in the construction of this power supply, however various radiation test campaigns have been performed in order to verify the reliability of these components. Active components were tested for total dose radiation damage and digital components were also tested for single event effects. The power supply architecture developed for the tracker detector has been used as a guideline for the development of the power supplies for the other detectors in the experiment

Hydrogenated amorphous silicon (a-Si:H) can be produced by plasma-enhanced chemical vapour deposition (PECVD) of SiH4 (Silane) mixed with Hydrogen. The resulting material shows outstanding radiation resistance properties and can be deposited on a wide variety of different substrates. These devices have been used to detect many different kinds of radiation namely: MIPs, x-rays, neutrons and ions as well as low energy protons and alphas. However, MIP detection using planar diodes has always been difficult due to the unsatisfactory S/N ratio arising from a combination of high leakage current, high capacitance and a limited charge collection efficiency (50% at best for a 30 &amp;micro;m planar diode). To overcome these limitations the 3D-SiAm collaboration proposes to use a 3D detector geometry. The use of vertical electrodes allows for a small collection distance to be maintained while conserving a large detector thickness for charge generation. The depletion voltage in this configuration can be kept below 400 V with consequent reduction in the leakage current. In this paper, following a detailed description of the fabrication process, the results of the tests performed on the planar p-i-n structures made with ion implantation of the dopants and with carrier selective contacts will be illustrated.

Abstract Tracking with silicon strip detectors for relativistic ions has been investigated using a 12 C beam of 1.5 GeV/ u at GSI. The ionization charge spectrum and the charge sharing between strips are presented. The strip cluster of carbon ion can be selected based on the cluster charge with high efficiency and little contamination. The spatial resolution of the silicon strip detectors is evaluated. The angular distribution of multiple Coulomb scattering was investigated with lead absorbers. The results are compared to the Moliere theory and the Gaussian approximation of GEANT calculations.

We have constructed and operated charge preamplifiers for silicon strip detectors with a dynamic range extending from fractions of minimum ionising particle (MIP) up to 16 124 MIPs. These silicon detectors combined with time-of-flight counters and cesium iodide scintillator form a segment of the VENUS detector that has been exposed to a calcium beam of 0.5 GeV/u at the GSI accelerator. The aim of the instrument is the identification of all nuclides of the periodic table of the elements. Measurements of electronic noise, cross-talk among channels and energy deposit resolutions in various experimental conditions for silicon detectors are given. The measured light output of the CsI(Tl) crystal induced by calcium is compared with that extrapolated from lower-energy data of various nuclide species determined in other experiments. The charge resolution for calcium ions, determined by the dEdχ detectors and TOF counters of time resolution of 55 ± 7 ps, amounts to 0.42 charge units (rms). Improvements in ion discrimination with respect to the present detector configuration are considered.

A Monte Carlo simulation of the cosmic rays interaction with the Earth’s atmosphere and magnetosphere has been developed. This simulation has been validated by a thoughtful comparison with the cosmic and undercutoff particle fluxes measured by the AMS experiment in 1998 at an altitude of ∼ 400 km. The results of our simulation are used to calculate the flux of secondary particles in the region above the AMS orbit and below the Van Allen belts (1000 km), where several experiments are scheduled to take data in the next years.

The operation of the present pixel detector has started in 2010 with LHC operating at a center of mass (CM) energy of 7 TeV. At the beginning of 2012 CM energy was increased to 8 TeV and within December 2012 a total of 19 fb <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> integrated luminosity has been delivered, with instantaneous peak luminosities approaching 7 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">33</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> . The present pixel detector was originally designed for a luminosity of 1 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">34</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> and a pileup (number of inelastic interactions per bunch crossing) of 25 in 25 ns bunch spacing. These beam parameters will be reached in the middle of the data taking period 2015-2018 (with an additional increase in the center of mass energy up to the value of 13 TeV) and then the peak luminosity will keep increasing until 2017 when it will reach the value of 1.5 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">34</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> . The present detector will remain operative until the end of 2016 and will be replaced with an upgraded detector that will be described in this work before Long Shutdown 2 (LS2). After LS2 the beam parameters will change again, around 2021 a peak luminosity reaching at least 2 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">34</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> is foreseen, consequently pile-up will increase up to 50 with 25 ns bunch spacing. In this context the present pixel detector will be unable to perform adequately and this is the reason why a new detector needs to be built and installed before LS2. The new upgraded detector will have higher tracking efficiency and lower mass with four barrel layers and three forward/backward disks to provide a hit pixel coverage up to absolute pseudorapidities of 2.5. In this paper the new pixel detector will be described focusing mostly on the barrel detector design, construction and expected performances. Test procedures for detector module production will also be presented.