Difference between revisions of "CDC algo tuning"

Revision as of 17:59, 4 December 2013

Using prototype data from CDC_50_50 (run 31924) with offline analysis

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

All thresholds found using upsampled data, with interpolation
Thresholds 5-4-1 pedlead 16 tz 7 tfix 1000	Thresholds 5-4-2 pedlead 16 tz 7 tfix 1000	Thresholds 5-4-3 pedlead 16 tz 7 tfix 1000

Event pedestal is mean of 100 samples ending at trigger time
Find hit threshold crossing
Upsample region around threshold crossing, with threshold crossing sample in set position
Step back <pedlead> points to find new pedestal
Search forward to find high threshold crossing
Search backward to find low threshold crossing
Project through both thresholds to find pedestal crossing time

High and low thresholds found using upsampled data, with interpolation
Thresholds 5-4-1 pedlead 16 tz 7 tfix 1000

Ideas

Check whether interpolating threshold xings makes any difference
Use the 3rd sample (or mean of 3rd & 4th samples) before hit threshold as local pedestal
Try reverting to one threshold crossing instead of the extrapolation
Try something easier for event pedestal - mean of 4 samples immediately before trigger

@@ Line 38: / Line 38: @@
 Ideas
 #Check whether interpolating threshold xings makes any difference
-#? Pass in hit pedestal to upsampling module, to find initial hit threshold xing better
+#Use the 3rd sample (or mean of 3rd & 4th samples) before hit threshold as local pedestal
-#Or interpolate around initial hit threshold xing and pass in number of 1/5 sample time?
 #Try reverting to one threshold crossing instead of the extrapolation
-#Try something easier for event pedestal
+#Try something easier for event pedestal - mean of 4 samples immediately before trigger