Difference between revisions of "CDC peak lengths"
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{| border="0" cellpadding="2" | {| border="0" cellpadding="2" | ||
− | |+Peak length in ch20, counting from threshold crossing to end of peak | + | |+Peak length in ch20, counting from lower threshold crossing to end of peak |
+ | |[[Image:pklength_bindiff10.png|thumb|x250px|peak ends at last sample which decreases by 10 or more]] | ||
+ | |[[Image:pklength_bindiff12.png|thumb|x250px|peak ends at last sample which decreases by 12 or more]] | ||
|[[Image:pklength_bindiff15.png|thumb|x250px|peak ends at last sample which decreases by 15 or more]] | |[[Image:pklength_bindiff15.png|thumb|x250px|peak ends at last sample which decreases by 15 or more]] | ||
|[[Image:pklength_bindiff20.png|thumb|x250px|peak ends at last sample which decreases by 20 or more]] | |[[Image:pklength_bindiff20.png|thumb|x250px|peak ends at last sample which decreases by 20 or more]] |
Revision as of 16:15, 23 February 2012
To find the peak (signal) length I have to decide where the peak ends and noise takes over.
Histogram of difference between adc sample value and previous sample value for first 190 samples in many events (trigger is approx sample 200 so samples 0-190 should be almost all noise).
Pedestal s.d is 11 (adc value) for these straws in this run. For other straws s.d. ranges from 9 to 13.
Sample value drop > 15 tracks/counts is 7478/11471 for sample value drop > 20, tracks/counts is 5960/11449