Noise scan

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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


New thresholds

A study with the new threshold setting is performed. Since GEMROC 0 FEB 2 is not properly calibrated, we have analysed GEMROC 4. Full detailed infomration can be found in the following file.

File:New threshold rate scan.pdf

In the following plots it is possible to find an example for FEB 16.

File:Occupancy tscan newTh.pdf

File:Ratestrip tscan newTh.pdf