F. Albiol

ATLAS beam test results

Abstract Many different configurations of electronics and semiconductor strip detectors were studied in 1995 using the ATLAS tracking detector test area at the H8 beam-line of the CERN SPS. A significant fraction of these investigations are presented elsewhere in this volume and this paper will concentrate on the results with silicon strip detectors read out with electronics preserving the pulse height information. Data has been collected with the ADAM, APV5 and FElix read-out chips on a number of different detectors. The first results are presented for read out with LHC electronics of detectors to the ATLAS-A specification of 112.5 μm pitch, employing n-strips in n-type silicon, capacitive coupling and intermediate strips. It is demonstrated that with adequate signal/noise, a spatial resolution of ⋍13 μm is attainable with these detectors.

First tests of the applicability of γ-ray imaging for background discrimination in time-of-flight neutron capture measurements

In this work we explore for the first time the applicability of using gamma-ray imaging in neutron capture measurements to identify and suppress spatially localized background. For this aim, a pinhole gamma camera is assembled, tested and characterized in terms of energy and spatial performance. It consists of a monolithic CeBr3 scintillating crystal coupled to a position-sensitive photomultiplier and readout through an integrated circuit AMIC2GR. The pinhole collimator is a massive carven block of lead. A series of dedicated measurements with calibrated sources and with a neutron beam incident on a Au-197 sample have been carried out at n_TOF, achieving an enhancement of a factor of two in the signal-to-background ratio when selecting only those events coming from the direction of the sample

Beam test of the ATLAS silicon detector modules

Abstract Results are reported from a beam test of prototype silicon microstrip detectors and front-end electronics developed for use in the LHC detector ATLAS. The detector assemblies (“modules”) were 12xa0cm long and were read out with binary electronics. Both irradiated and unirradiated modules were measured in a 1.56xa0T magnetic field for efficiency, noise occupancy, and position resolution as a function of bias voltage, binary hit threshold, and detector rotation angle with respect to the beam direction.

BEAM TEST of the ATLAS SILICON DETECTOR MODULES with BINARY READOUT in the CERN H8 BEAM in 19961

detector with small angle stereo readout. Readout will be AC-coupled from n-type implant strips in n-bulk crystals. increased depletion voltage [3], the junctions will be at the nstrips allowing the possibility of operation under partial depletion of the silicon. The readout electronics [4] employs a 1 bit binary scheme whereby only hits above a single threshold are recorded. In such a scheme the required resolution is achieved with 75pm pitch detectors. Noise OccuPancY must be well below not to exceed the bandwidth of the data transmission system. A key Derformance reauirement of such a system is to maintain are reprted from a beam test Of Prototype After radiation induced type inversion of the bulk and micro strip detectors and front-end electronics designed for use at the LHC. The detector assemblies were 12 cm long and were read out with binary electronics. Both irradiated and unirradiated assemblies were measured in a 1.56T magnetic field for efficiency, noise occupancy, and resolution as a function of bias voltage, binary hit threshold, and detector rotation angle with respect to the beam direction. Measurements were also performed at a particle flux comparable to the one expected at the LHC.

Performance of the ATLAS silicon strip detector modules

Abstract The performance of the silicon strip detector prototypes developed for use in ATLAS at the LHC is reported. Baseline detector assemblies (“modules”) of 12 cm length were read out with binary electronics at 40 MHz clock speed. For both irradiated and unirradiated modules, the tracking efficiency, noise occupancy, and position resolution were measured as a function of bias voltage, binary hit threshold, and detector rotation angle in a 1.56 T magnetic field. Measurements were also performed at a particle flux comparable to the one expected at the LHC.

Silicon detectors for forward tracking in ATLAS

Abstract A 12 cm long silicon microstrip detector module with a fan geometry has been designed and constructed. The performance of the detector has been studied in a test beam at CERN. Results are presented on the hit efficiency and the position resolution as a function of position along the strips. With a hit efficiency of 99.5% and a spatial resolution of typically 35 μm the performance of these detectors exceeds that of other candidate technologies for the precision forward tracker of the ATLAS inner detector.

Pulse height of MIP's in an n-side silicon microstrip detector after proton irradiation with a fluence of 1x10**15 p cm**(-2)

We have irradiated an n-side silicon microstrip detector to an equivalent high energy fluence of 1/spl times/10/sup 15/ p cm/sup -2/ using 55 MeV protons. We determined the median pulse height to be 0.7 fC at a bias voltage of 180 V, and deduced a depletion region of about 80 /spl mu/m.