Results from irradiation tests on D0 Run 2a silicon detectors at the Radiation Damage Facility at Fermilab

Abstract

Several different spare modules of the D0 experiment Silicon Microstrip Tracker (SMT) have been irradiated at the Fermilab Booster Radiation Damage Facility (RDF). The total dose received was 2.1 MRads with a proton flux of ~3·10 11 p/cm 2 sec. The irradiation was carried out in steps of 0.3 or 0.6 MRad, with several days between the steps to allow for annealing and measurements. The leakage currents and depletion voltages of the devices increased with dose, as expected from bulk radiation damage. The double sided, double metal devices showed worse degradation than the less complex detectors.

Measurement of the W and Z Cross Sections in the Electron Channel for p¯p Collisions at √s = 1.96 TeV and Extraction of the W Total Width from the Ratio

“…These shower shape cuts are necessary in order to reduce the L3 output rate while keeping the E T threshold below the 25 GeV cut used in this analysis. The L3 trigger condition ELE LOOSE(1, 30) does not have shower shape cuts and must therefore have a 30 GeV E T threshold while ELE LOOSE SH T(1,20), with shower shape cuts, has the threshold reduced to 20 GeV. Due to increasing luminosity, the CMT 12 trigger condition ELE NLV SH(1,30), which has loose shower shape cuts, must also have a 30…”

“…L1 trigger conditions CEM(1, 10) one EM trigger tower with E T > 10 GeV CEM(2,5) two EM trigger towers with E T > 5 GeV CEM(1,15) one EM trigger tower with E T > 15 GeV CEM(1,11) one EM trigger tower with E T > 11 GeV CEM(2, 6) two EM trigger towers with E T > 6 GeV CEM(1,9)CEM(2, 3) one EM trigger tower with E T > 9 GeV, another EM trigger tower with E T > 3 GeV L2 trigger conditions EM(1,12) one EM candidate with E T > 12 GeV (not present for runs below 169524) L3 trigger conditions ELE LOOSE SH T(1,20) one electron with |η det | < 3.0, E T > 20 GeV, EM fraction > 0.9 and passing shower shape cuts ELE LOOSE(1, 30) one electron with |η det | < 3.0, E T > 30 GeV and EM fraction > 0.9 ELE NLV SHT(1, 20) one electron with |η physics | < 3.6, E T > 20 GeV, EM fraction > 0.9 and passing tight shower shape cuts ELE NLV SH(1, 30) one electron with |η physics | < 3.6, E T > 30 GeV, EM fraction > 0.9 and passing loose shower shape cuts for CC,…”

“…Effects after exposure such as increased leakage current which can reduce the size of the depletion region are measured. This was carried out for Run II silicon modules [30] and also for a proposed silicon detector upgrade for Run IIb [31].…”