CDC algo status

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Add simplifications to offline code to show impact

Using prototype data from CDC_50_50 (run 31942) with offline analysis

50/50 Ar/CO2 and cosmics, 2100V, prototype horizontal

Only 20 samples upsampled
  1. Event pedestal is mean of 100 samples ending at trigger time
  2. Find hit threshold crossing
  3. Upsample 20 samples starting 10 before hit threshold crossing
  4. Find hit threshold crossing again in upsampled data
  5. Step back <pedlead> points to find new local pedestal
  6. Search forward to find high threshold crossing
  7. Search backward to find low threshold crossing
  8. Project through both thresholds to find pedestal crossing time
Thresholds 5-4-1 pedlead 16 tz 7 tfix 1000


Selected results below

more details here

Simplifications (one at a time)
Event pedestal is mean of 4 samples
Local ped mean of 4 and 5 samples before hit threshold


Combined simplifications
(a) Event ped is mean of 4 samples, local ped is mean of 4 and 5 samples before hit_thr
(b) As left, but no interpolation when finding high and low thresholds
(c) As top left, hit time is interpolated low threshold crossing time
(d) As top left, hit time is low threshold crossing time without interpolation

Lower line (c and d) are from single threshold crossings