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A. Papi

Publications and source records attributed to A. Papi.

6 recordsLinked to original sources

Proton irradiation on Hydrogenated Amorphous Silicon flexible devices

Radiation damage tests in hydrogenated amorphous silicon (a-Si:H) flexible flux and dose-measuring devices have been performed with a 3 MeV proton beam, to evaluate combined displacement and total ionizing dose damage. The tested devices had two different configurations and thicknesses. The first device was a 2 um thick n-i-p diode having a 5 mm x 5 mm area. The second device was a 5 um thick charge selective contact detector having the same area. Both the devices were deposited on a flexible polyimide substrate and were irradiated up to the fluence of 1016 neq/cm2. The response to different proton fluxes has been measured before irradiation and after irradiation at 1016 neq/cm2 for charge-selective contacts and n-i-p devices. The effect of annealing for partial performance recovery at 100{\deg}C for 12 hours was also studied and a final characterization on annealed devices was performed. This test is the first combined displacement and total ionizing dose test on flexible a-Si:H devices.

physics.ins-det

Characterization of hydrogenated amorphous silicon sensors on polyimide flexible substrate

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.

physics.ins-det

Development of thin hydrogenated amorphous silicon detectors on a flexible substrate

The HASPIDE (Hydrogenated Amorphous Silicon PIxels DEtectors) project aims at the development of thin hydrogenated amorphous silicon (a-Si:H) detectors on flexible substrates (mostly Polyimide) for beam monitoring, neutron detection and space applications. Since a-Si:H is a material with superior radiation hardness, the benefit for the above-mentioned applications can be appreciated mostly in radiation harsh environments. Furthermore, the possibility to deposit this material on flexible substrates like Polyimide (PI), polyethylene naphthalate (PEN) or polyethylene terephthalate (PET) facilitates the usage of these detectors in medical dosimetry, beam flux and beam profile measurements. Particularly interesting is its use when positioned directly on the flange of the vacuum-to-air separation interface in a beam line, as well as other applications where a thin self-standing radiation flux detector is envisaged. In this paper, the HASPIDE project will be described and some preliminary results on PI and glass substrates will be reported.

physics.ins-det

Testing of planar hydrogenated amorphous silicon sensors with charge selective contacts for the construction of 3D- detectors

Hydrogenated Amorphous Silicon (a-Si:H) is a material well known 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 (SiH4) 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.

physics.ins-det

The integrated low-level trigger and readout system of the CERN NA62 experiment

The integrated low-level trigger and data acquisition (TDAQ) system of the NA62 experiment at CERN is described. The requirements of a large and fast data reduction in a high-rate environment for a medium-scale, distributed ensemble of many different sub-detectors led to the concept of a fully digital integrated system with good scaling capabilities. The NA62 TDAQ system is rather unique in allowing full flexibility on this scale, allowing in principle any information available from the detector to be used for triggering. The design concept, implementation and performances from the first years of running are illustrated.

physics.ins-det

Fast trigger logic with digitized time information

We present a method for the evaluation, at the first level of trigger, of logical conditions with high time resolution, using the digitized times of fast signals delivered in the detectors of high rate experiments. We describe a dead-time-less implementation of this method on a commercial Field Programmable Gate Array (FPGA). By virtue of its features, the method offers an excellent solution to the problem of including veto conditions in the first level of trigger for experiments on rare decays.

physics.ins-det