Simulation of signal and noise after irradiation

The noise and signal of a silicon sensor considering:

  • 200 μm sensor thickness
  • Seed signal from orthogonal MIP
  • Landau MPV = 12000 e- * exp(-irrad/4.048e15 neq)
  • Landau width = 9% * MPV
  • Gaussian noise distribution
The signal MPV is computed, taking into account a 200 um silicon, with a magnetic-Czochralski-like annealing (i.e. no significant signal loss). Signal amplitude MPV is obtained from a fit of the HPK measurements on "seed signal" as presented by Alexander Dierlamm here. The range of validity of the fit covers the outer tracker volume as shown in the picture below.
Based on this the expected signal inefficiency and noise occupancy are computed for a range of binary thresholds between -5000 and 30000.
Also, considering a pT-finding module, the probability of finding a noise stub is computed, which is reported as "Noise occupancy (stub)". The probability of detecting both hits from a high-pT track is also computed (as efficiency^2) and is reported as "Signal inefficiency (stub)".