Issue

Xiaozhe complains that too many pixels outside signal region in ueddaq02 r401 shows up in selection of intensities between 100 and 500 keV.

Case of run 401

Issue demo

det.raw.calib(evt) for ueddaq02 r401, selection of intensities between 100 and 500 keV

Check correctness of loaded calibration constants

metadata consistent with last dark run ueddaq02 r398 for pedestals, pixel_gaim, pixel_rms, pixel_status:

pedestal metadata: {'_id': '6049c3c1baf79f747df38a05', 'experiment': 'ueddaq02', 'run': 398, 'run_end': 'end', 'detector': 'epix10ka_000001', 'ctype': 'pedestals', 'dtype': 'ndarray', 'time_sec': '1615182592', 'time_stamp': '2021-03-07T21:49:52-0800', 'version': 'V2021-03-04', 'comment': 'no comment', 'uid': 'xshen', 'host': 'psanagpu102', 'cwd': '/cds/home/x/xshen', 'id_data': '6049c3c1c88c56b170aaf7b3', 'id_doc_exp': 0, 'id_data_exp': 0, 'detname': 'epixquad', 'longname': 'epix10ka_3926196238-0175152897-1157627926-0000000000-0000000000-0000000000-0000000000_3926196238-0174824449-0268435478-0000000000-0000000000-0000000000-0000000000_3926196238-0175552257-3456106518-0000000000-0000000000-0000000000-0000000000_3926196238-0176373505-4043309078-0000000000-0000000000-0000000000-0000000000', 'shortname': 'epix10ka_000001', 'dettype': 'epix10ka', 'run_orig': 398, 'tstamp_orig': '2021-03-07T21:49:52-0800', 'extpars': '{"content": "extended parameters dict->json->str", "command": "/cds/home/opr/uedopr/git/lcls2_210310/install/bin/epix10ka_deploy_constants -e ueddaq02 -d epixquad -r398 -D -L INFO"}', 'data_type': 'ndarray', 'data_dtype': 'float32', 'data_size': '3784704', 'data_ndim': '4', 'data_shape': '(7, 4, 352, 384)'}

Basic plots

Panel index 0-3, gain range index for event 5 is 2 (FL), Gain factor(for grind=2) 0.164

RMS(FL), pedestals(FL), raw for event 5, 

Event 5: raw-peds (ADU), (raw-peds)/gain (keV), calib (keV)

Event 5 (raw-peds)/gain (keV) for hot and cold ASICs

Summary

• constants for ueddaq02 r401 are loaded correctly from the latest dark run r398
• default gain factor for FL is 0.164 ADU/keV (or ~6 keV/ADU)
• numeration of panels is defined in geometry looks correct
• per-pixel gain range index is defined correctly =2 for FL.
• pedestal subtraction works as expected: raw-peds has mean=0.6 ADU, raw RMS shrinks from 170 ADU to ~3 ADU raw-peds.
• there may be a minor common mode offset ~0.6ADU, but common mode is not corrected for FL. Even if it is corrected, this would not resolve this issue.
• default gain factor is defined correctly for FL is 0.164 ADU/keV
• rms defined in dark r398 shows that panel/banks have significant spread/noise variation of factor 2-3 between panels.
• plots of calib for "hot" and "cold" ASICs show that RMS is significantly different. 
• in this case application of the common threshold is a bad idea

Recommendations

• Check if hardware could be set to perform more uniformly in terms of noise/rms spread
• At analysis level use per-pixel thresholds defined in terms of "number of dark RMS".

Case of runs 553-558

New dark data collected in ueddaq02 to check improved detector performance

Dark run 553 processing results

RMS for different gain modes of runs 554-558

pedestals for different gain modes of runs 554-558

First 10 events det.raw.calib for different gain modes of runs 554-558

Summary

• epixquad in runs 553-558 behaves much better than in runs 398, 401
• rms after dark processing of the run 553 are almost the same for all banks in all gain modes
• two threshold algorithm applied in run 401 should work in this case, but all of collected runs were dark, without signal.
• all images show damage of the detector in segment 1 near detector center.

References

• EPIX10KA2M References