A. Webster

A fast shaping low power amplifier-comparator integrated circuit for silicon strip detectors

We have designed and tested a 64 channel amplifier-comparator integrated circuit on the Maxim SHPi bipolar process. The low power design, 840 /spl mu/W/channel, is intended for use as a frontend with high clock rate silicon strip detector systems. Peaking time at the comparator input is 20 ns, for good double pulse resolution, and noise is near optimum for the technology used. We have used the chip successfully in a proton beam test at KEK in Japan with a 40 MHz data clock. >

Development of radiation-hard materials for microstrip detectors

We present the search for new detector materials, which would replace silicon as the bulk material in strip detectors for application in high radiation fields. The investigation focuses on SiC, a material with higher bandgap and thus less degradation after irradiation when compared with silicon. Both static properties like the capacitance and leakage currents and dynamic measurements of the charge collection with low-noise amplifiers are presented.

Signal-to-noise in silicon microstrip detectors with binary readout

We report the results of a beam test at KEK using double-sided AC-coupled silicon microstrip detectors with binary readout, i.e., a readout where the signals are discriminated in the front-end electronics and only the hit location as kept. For strip pitch between 50/spl mu/ and 200/spl mu/, we determine the efficiency and the noise background as function of threshold setting. This allows us to reconstruct the Landau pulse height spectrum and determine the signal/noise ratio. In addition, the threshold/noise ratio necessary for operation with low occupancy is determined. >

The silicon tracker of the beam test engineering model of the GLAST large-area telescope

The silicon tracker for the engineering model of the GLAST Large Area Telescope(LAT) has at least two unique features: it employs self triggering readout electronics, dissipating less than 200 mu-W per channel and to date represents the largest surface of silicon microstrip detectors assembled in a tracker (2.7 m{sup 2}). It demonstrates the feasibility of employing this technology for satellite based experiments, in which low power consumption, large effective areas and high reliability are required. This note describes the construction of this silicon tracker, which was installed in a beam test of positrons, hadrons and tagged photons at SLAC in December of 1999 and January of 2000.

Beam tests of a double-sided silicon strip detector with fast binary readout electronics before and after proton-irradiation

Abstract A double-sided silicon strip detector with a radiation-tolerant design was fabricated and characterized in a sequence of beam tests at KEK using 4 GeV/ c pions. The detectors were combined with newly designed, fast, lower power, bipolar amplifier-shaper-discriminator chips and CMOS digital pipeline chips to record hit-no hit signals in the strips. Efficiencies, noise occupancies, and spatial resolutions were measured before and after the proton irradiation at an equivalent fluence of 1 × 10 14 p/cm 2 , depending on angle of track incidence and strip-pitches. The median pulse height distribution, derived from the threshold scans of the efficiency, allowed to extract the response of the detector. A 1 T magnetic field enabled us to determine the Hall mobilities of electrons and holes.

Beam Test Of The SDC Double-sided Silicon Strip Detector

A beam test was executed to evaluate the behavior of the first prototype radiation-hard double-sided silicon microstrip sensor for the SDC silicon tracking system. Pions of 4 GeV/c in a test bcamline at KEK illuminated three planes of detectors. Thc signals wcrc amplified, shaped, and discriminated with TEKZ bipolar analog LSIs, and the on-off levels were sampled at l0MHz clock with CMOS digiwl LSIs, asynchronously with beam triggers. The detectors were rotated in null and 1 .O Tesla magnetic fields. The efficiencies were found to be 98-9996. The position resolutions were 12.5pm. where the multi-strip hit fraction was 30-40%. There was no essential difference in the performance of the pand the n-sides. The multi-strip hit fraction showed a clear rotation and magnetic-field dependence. From the angles where the fractions were minimum in the 1T magnetic field, the Hall mobilities of the electrons and holes were obtained to be 1391k43 (clcctrons) and 325f30 (holes) cm2/Vs.

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.

Testing and installation of ZEUS Leading Proton Spectrometer detector planes

Abstract The assembly and testing of the components which make up a detector plane for the Leading Proton Spectrometer is described. The spectrometer, a part of the ZEUS detector, utilizes single-sided DC-coupled silicon strip detectors and custom VLSI front-end electronics for readout.

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 detector-pyrolytic graphite sandwich

We have conducted thermal measurements on a thermal prototype of a novel concept to construct silicon modules, using thermally conductive Pyrolytic Graphite as a heat spreader sandwiched between two single-sided silicon detectors. We have measured the temperature profile as a function of heating power at a coolant temperature of -10/spl deg/C and ambient temperatures of 0, -5, -10/spl deg/C and found that the temperature increase of the silicon detectors is below 3/spl deg/C for realistic power levels.