HV Scan Fall 2016

HV Scan Fall 2016

In order to determine the HV settings for the TOF PMTs a scan of the HV for all PMTs needs to be performed with the following conditions:

• verify that the DAC values are set such that the base line for all PMTs is at about 100 ADC counts
• all thresholds for the discriminators should be set at -10. This value will correspond to about 10mV above base line in the TDC.
• the ADC readout window should be set to 100 samples
• NSA 25 samples
• NSB 3 samples
• CAEN TDC readout window should be large like 3000ns to include random hits to test integral non linearity correction

The following HV settings should be use for the scan

1. All HV at 1200 V (nominal)
2. All HV at -25V of nominal
3. All HV at +25V of nominal
4. All HV at -50V of nominal
5. All HV at +50V of nominal
6. All HV at -75V of nominal
7. All HV at +75V of nominal
8. All HV at -100V of nominal
9. All HV at +100V of nominal