stevens4's blog

The pedestals and status tables from the 200 GeV portion of Run 10 were determined using the L2 pedestal algorithm output (generated online) that is saved on the "online machines" during data taking. The L2 pedestal algorithm is attached to a minimum bias trigger during data taking and provides a raw ADC distribution for each tower. Summing these raw ADC distributions over several runs within a fill provides enough statistics to determine the towers pedestal value, and check the status of the tower. This procedure results in at least one pedestal and status table per fill and sometimes more.

There is a summary here of the runs used to generate the pedestal and status tables, as well as the (ped subtracted) ADC distributions for all 4800 towers for each table. By clicking the "BTOW" link for each row you can see the individual ADC distributions in a PDF file.

Alice Ohlson and Elena Bruna did some very helpful QA of the status tables, including checking how many times towers changed status over the course of the entire 200 GeV running period and checking if those changes in status are real changes in tower behavior, or just a problem with how the status was determined. After a few iterations we converged on the final tables.

Attached below is a .csv file which lists the towers that have status!=1 for each status table available. I hope this is close to the "fix-it" list Oleg requested.

Note: Before run 11028004 the L2 algos were not running so the raw ADC distributions (from vpd-mb trigger) were generated with the daqReader from daq files. The pedestal and status tables were determined using the same status checking algorithm, just the input was not from the L2Ped algorithm but instead from daq files for these early runs.

To Do:

- Load tables to DB

- Check-in code to CVS

Below are the status code definitions (same as previous years) and some example tower ADC spectra

Status Code Definitions
000 == channel does not exist or is masked in L2ped
001 == channel is good
002 == channel is either hot or cold (see bit 16)
004 == channel has a weird pedestal (see bit 32)
008 == channel has a stuck bit (see bits 64 and 128)
016 == if off, hot (10x as many hits); if on, cold tower (10x fewer hits)
032 == if off, pedestal mean is out of bounds; if on, pedestal width is too large/small
064 == bit stuck on
128 == bit stuck off
254 == identical channel

Some plots of example towers (all distributions are pedestal subtracted):

Good Tower