S. Pier

Test results on silicon micro-strip detectors for ATLAS

We report results from beam tests on silicon microstrip detectors using a binary readout system for ATLAS. The data were collected during the H8 beam test at CERN in August/September 1995 and the KEK test in February 1996. The binary modules tested had been assembled from silicon microstrip detectors of different layout and from front-end electronics chips of different architecture. The efficiency, noise occupancy and position resolution were determined as a function of the threshold setting for various bias voltages and angles of incidence for both irradiated and non-irradiated detectors. In particular, the high spatial resolution of the beam telescope allowed the evaluation of the performance as a function of the track location in between detector strips.

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.

Monitoring the performance of silicon detectors with binary readout in the ATLAS beam test

The monitoring of the performance of silicon strip systems with binary readout is discussed. Due to the fact that neither pulse height nor noise level are recorded, the system is monitored with the efficiency and noise occupancy. As an example, on-line monitoring of the binary silicon strip system at the ATLAS H8 beam test at CERN is described.

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.

Performance of the binary silicon system for ATLAS

We report on the results from a beam test of a binary silicon strip system proposed for ATLAS. The data were collected during the H8 beam test at CERN in 1995 and at a beam test at KEK in 1996. The binary modules tested had been assembled from silicon micro-strip detectors of different layout and from front-end electronics chips of different architecture. The efficiency, noise occupancy, and position resolution were determined as a function of the threshold setting for various bias voltages and angles of incidence. Interstrip effects were also evaluated using a high resolution telescope. The performance of a prototype detector module irradiated to a fiuence of 1.2 × 10 14 p/cm 2 is also characterized.

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.