We mounted the new S1 detector from Surrey with a new custom cable on several MUFEE cards using the CsI ASICs.
We managed to put voltage on it and get decent leakage current.
We modified the DAS parameters from CsI values to Si values (gain, shaping time, etc).
However as soon as we enable a S1 channel, we get a very large increase of trigger rate (ORD of several 10000) creating huge dead time. Nothing apart pedestal is visible on the energy spectra.
After investigation with Charles and Fred we believe that there is a noise (detector/cable, maybe at high frequency) that goes on the decision chain in the asic (with fast shaper) but that this noise is filtered on the energy coding chain (by the slow shaper) and thus invisible after the ASIC (even with the scope on the analog using the inspection lines).
We give up on S1 and proceed only with 6 working trapezoids and 5 MUST2. |