Richard Nickerson

Abstract:

The results of an accelerated life time test of neutron irradiated ABB Hafo radiation hard LEDs are presented. After a 1 MeV neutron irradiation with up to 1.4 × 1014 n/cm2 at the Rutherford Appleton Lab (RAL) ISIS facility, the LEDs have been operated without seeing any degradation due to ageing for a time which is estimated to correspond to about 57 years of operation in the ATLAS Semiconductor Tracker (SCT) at the Large Hadron Collider (LHC). The irradiation decreased the light output of the LEDs substantially, but during the operation of the LEDs a fast annealing of most of the irradiation damage was observed.

Abstract:

We have used the energy-energy angular pattern of hadrons in inelastic muon-deuteron scattering to study perturbative QCD effects and to extract the gluon distribution function ηG(η) of the nucleon, where η is the fractional momentum carried by the gluon. The data were taken with the E665 spectrometer using the Fermilab Tevatron muon beam with a mean beam energy of 490 GeV. We present ηG(η) for 0.005 < η < 0.05 and at an average Q2 of 8 GeV2 using this new technique. We find that ηG(η) in this region can be described by ηG(η) ∝ ηλ with λ = -0.87±0.09(stat.)±0.370.32(sys.). We compare our results to expectations from various parametrizations of the parton distribution function and also to results from HERA. © Springer-Verlag 1996.