FEE/FERA ADC Tests
In an effort to test the FERA/FEE ADC linearity and conversion, subsector 6TC was pulsed by the LED system and read out by first the FEE and then the FERA ADC. This test was repeated for 8 HV settings ranging from 800-1150 in 50 V increments. The LED was pulsed at an amplitude of 1700 and the LED delay was set to 50ns (timing was determined to be independent of voltage +/- 5ns). The FERA gate was set to 250ns.
Data table of Towers vs HV for FEE LED peak mean (ped subtracted)
Data table of Towers vs HV for FEE LED peak sigma
Data table of Towers vs HV for FERA LED peak mean (ped subtracted)
Data table of Towers vs HV for FERA LED peak sigma
The FEE and FERA led data were manipulated into the form:
(LED PEAK/100) = A * (Voltage/1000)B
The equation above was plotted for each tower for all voltages. A fit was then used to extract B for both the FEE and FERA setup. The plot below shows the correlation between B for the FERA and the FEE for each tower in 6TC. They are highly correlated (which is good) and = 8.2-8.4.
Plotting FEE vs FERA led peak mean for towers 1,6,10 and 11 gives a conversion of 4 - 4.5
A more careful analysis shows the conversion gain to be 4.3 -- exactly as Gerard calculated. The plot below shows the correlation between "A" (see equation above) for the FEE and FERA.
Output files, *.evt files and plots located at ~online/mini/alpha on eemc-sc.starp.bnl.gov
kumac used to create output files for FEE
kumac used to create output files for FERA
kumac used to produce plots and data tables