Update 18 July

Efficiency problem

The tracking efficiency of the layers is between 60 and 70%.

The tracking efficiency seems to do not depend on the HV.

The trigger match efficiency is above 95%.

Injecting signal on 3 strips we measure 100% of the cluster but only 91% is perfectly reconstructed.

Injecting signal on 1 strips we measure it with an efficiency of 90-97% (compatible with the trigger match test).

There is a missing part to understand the efficiency and to fill the gap between the 90% observed by the electronics and readout efficiency and the 70% of the detector.

1. Continue with the hardware MC test injecting 1 or 3 strips plus the noise on each channel
2. Did we test the difference between the ROC count and the trigger counter count? --> DONE: Matching ~ 98%
3. Acquire a longer cosmic run to increase the statistic
4. Write a code to selected the good cluster as the one with the minimum chi2 --> DONE: Efficiency improve of ~ 5% but alignment is needed to improve this technique
5. Perform a trigger-less test to collect all the data and measure the efficiency of the detector

Charge problem

The charge collected on the detector is lower than 30-35 fC with respect to previous configurations.

Threshold level seems be unchanged (within 1fC).

The charge hits distribution around 5-12 fC is lower.

Work on data and software studies:

1. Insert a software threshold on the RUN 134 to match the results of run 139: DONE --> Software THR scan DO not confirm our hypothesis
2. Compare the charge distribution difference FEB by FEB (or layer by layer) between run 134 and 139: DONE -> different distribution
3. Compare the charge distribution of the strip with the larger charge in the cluster: DONE -> different distribution
4. Compare the charge distribution difference event by event between run 134 and 139: DONE
5. Measure the noise level on Layer 1 from the TB data --> DONE: Mean std 15 ADC. Up to 30 ADC (1 fC). Mean sigma 3, up to 6. Then on average the threshold on L1 was 1.5 fC
6. Compare the number of saturated hit between TIGER-ROC/APV: DONE -> APV ~ 5% at 270V on L1 // TIGER ~ 6% at 275V RUN 134 // TIGER ~ 3% at 275V RUN 139
7. Test the behavior of the dead channel settings --> It was 1. Changing it to 3 it does not change so much the results

Work on electronics and configuration studies:

1. Measure the rate channel by channel to monitor it
2. Perform more TS, random trigger and cosmic as a routine

Possible configuration for the data taking:

1. Reduce the threshold cut up to reasonable level (5-10 kHz/channel ?) to be more sensitive to low charge hit
2. Increase the HV on the detector if we have the chance to monitor Layer1 since it is very unstable

Rate measurement on the run of interest:

1. Run 134(T=3 E=2): 2 kHz/channel
2. Run 139(T=3 E=2): 170 Hz/channel
3. Run 154 (same of 134): 190 Hz/channel
4. Run 150 (T=2 E=1): 285 Hz/channel
5. Run 219 (T=2 E=1): 3 kHz/channel

The RUN 134 (labelled as the good one) has an higher noise (10 times larger) then the larger charge value is explained in this way