Status of CLAS Cerenkov detector calibrations

Amplitude (SPE) calibrations :

A set of SPE (Single PhotoElectron amplitude) calibrations were made during g8 and the beginning of the g6 runs, - runs ## 29100, 29355.
It was found, that most SPE peaks are at the same position, as in January,2001.
HV were corrected to adjust SPE peaks to the
value of 200 channels. After that the another SPE calibrations were made (Run #29415).

All calibrations were stored in the default database (CALDB).

Almost all channels are well - calibrated. There are 9 channels , where it was difficult to define the SPE peak. In order better definition of SPE peak a set of calibration runs with different HV settings were made. Only those 9 channels were enabled during the run to enlarge statistics.
HV settings were : Nominal value, +50V., +100V., +150V., -50V. and -100V. The task was to define SPE ( if possible) at different HV settings and find the HV for SPE = 200 channels. SPE peak was extracted by fitting both by simple Gauss and by Gauss + Exp (noise function).

Channels 1-19 and 2-21

Channels 4-5 and 5-9

Channels 5-14 and 5-25

Channels 5-32 and 6-30

Channel 6-32

Cerenkov detector calibrations, Feb, 2004

Cerenkov detector calibrations, Feb, 2004 :

Latest SPE calibrations shows that some channels are difficult to calibrate, and some are IMPOSSIBLE to calibrate (VERY Bad ones)
Status for different channels is shown on the fig. CC calibration status

Cerenkov Time calibrations :

Preliminary T0 and T1 constants were set to calibration database. I expect that NTUPLEs with Cerenkov time information will be available soon for eg1b run. The program to read these NTUPLEs and to adjust calibration constants then will be tested.