Difference between revisions of "Noise scan"

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- noise rate: hit_event divided by DAQ time. It is the rate of noise per strip.
 
- noise rate: hit_event divided by DAQ time. It is the rate of noise per strip.
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In the following plots it is possible to find an example for FEB 0.
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[[File:Rate strip tscan.pdf|thumb|Rate per strip at different values of T  and E branch thresholds]]
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[[File:Occupancy tscan.pdf|thumb|Occupacy at different values of T and E branch thresholds]]

Revision as of 09:45, 29 May 2019

Using the information from the threshold scan it is possible to give an estimation of the noise, expressed both in occupancy (%) and in rate (Hz).

The following file contains the detailed information for all the investigated FEBs. FEB2 data are missing since it is not properly calibrated.

File:Noise scan.pdf

Some information on the variable used:

- noise: number of hits with charge > 2 fC and in a time window of -100 < t < 200 ns around the trigger time

- total: number of events in each run

- DAQ time: 300 ns time window times the number of events. It is the total time considered.

- hit_event: ratio between noise and total

- occupancy: hit_event divided by the number of channels (in the runs 63-87, 124 channels per each FEB) multiplied by 100.

- total noise: noise divided DAQ time

- noise rate: hit_event divided by DAQ time. It is the rate of noise per strip.

In the following plots it is possible to find an example for FEB 0.

File:Rate strip tscan.pdf

File:Occupancy tscan.pdf