SoLID Ecal Weekly 20230713

Update from Spencer

Showed plots of simple position and angular cuts.
Simple tracking doesn't seem to change the shape of the timing distributions for LASPD_t-LASPD_b and SC_D-SC_C.
For timing of SC-D minus SC-C. Fitted sigma is about 584ps. For LASPD Top - Bottom, about 2726 ps. Note that the bin size of the edge finding algorithm is 4ns/64 = 62.5 ps. With LASPD intrinsic timing resolution of 150 ps (based on previous study), we might see a couple of 100ps but not 1E3 ps level.
Will try to make some tighter tracking cuts, as well as a smaller timing window.
Suggest reading through Jixie's work on LASPD timing from cosmic test, latest one reported on 11/16/2017 ECal meeting, look for correlation between timing and our GEM tracking position and see if we can do the same position correction
Want to achieve LASPD timing resolution of 150ps or better.

Showed evidence that the source of the low-NPE blob is caused by electrons that have 0 momentum on the virtual plane of SC-A, potentially caused by scattering. 1D Hist 2D Hist
Still more questions about the start of the momentum distributions (at the event generator level), but Ye Tian was checking this.
Will start working on full sim to have a classifier ready for when samples are selected by Mike/Ye Tian.

Update the Shower L,T,R,sum distributions for the beam current scan with LD2 at 70uA (cut off the beam trip events). The shower_l distributions with/without beam trip cut are quite different. It turned out that the left module died at 70uA, see page 1 and 2 of the slides

Beside high energy spectrum problem, there is an MIP "shift" (see page 8 of the above slides) between different beam currents. The "shift" is consistent with amplitude changes of the waveform signals (decoder is okay). Furthermore, the ratio between left, right and top modules had been changed as well ( The simulation shows that the distributions from the three shower modules are balanced when the beam hit the center of detectors). Need to check the gain shift between different runs (as mentioned by Tim previously).

Tried to compare the MIP peak between the 5uA data and simulation, and the agreement is not as good as the high energy spectrum (simulation/data>3). More carefully study need to apply on this kind of comparison (MIP calibration, shower).