Quick and dirty BSMD saturation simulation

Following some discussion in the EMC group on BSMD gain settings, I wanted to see what information is stored in the side strips even if the central strips in an SMD get saturated. This is not meant to be definitive, but rather a basic proof of principle, which may be old news to some people.


I wrote a brief simulation assuming:

  1. All clusters have the same intrinsic profile: a Gaussian of width 0.7 strips, which means the center strip has about 60% of the cluster's total energy (clusters are centered on a single strip in this basic simulation).
  2. Strip energy measurements saturate at the response they would give if they were the central strip for a 12 GeV particle.
  3. Before saturation, all responses are linear with particle energy.

The results are as follows:

  • Top: fraction of cluster energy in each strip as a function of strip distance from central strip.
  • Middle: Cluster energy sum and RMS versus incident energy (saturation affects cluster sum for all high incident energies, but the RMS becomes a source of information).
  • Bottom: A function I invented using the energy of the first non-saturated strip ("StripE") and the number of saturated strips ("Strip") which is monotonic and nearly linear with incident energy.

This simple simulation did not include the strip energy uncertainties. I don't know how the resolutions in side strip responses vary with incident particle energy.

Regardless, I think this is proof of principle that saturation of response in the central strip(s) does not mean information is completely lost about the incident particle energy.