Run 7 BTOW Calibration

Online Work

Steve T's page:

First Iteration

March 27, 2007

Steve and Oleg took 600k fast events in runs 8086057, 8086058, and 8086060 to calculate the tower slopes.  Here's a summary plot of tower slopes vs. eta:

I've attached two list of slopes for each tower at the bottom of the page.  The columns are

id -- flag -- slope -- error -- chi2 -- ndf

where the flag is determined by

if(ndf < 30) x                        //empty, stuck bit
else if(chi2 > 200.) ?               //worth a closer look
else if(slope outside 4*RMS) *   //probably needs HV adjustment
else blank                             //channel OK at 4*RMS level

The file slopes_noflags.txt has the same data as the first file, but it omits all the flag information so that it can be read into a macro easily.  Flagged channels are also listed in red in the mega-PDF

Second Iteration

Same procedure as  First Iteration.  Took 600k events in runs 8089017, 8089019, 8089021.  This time the processing went smoothly and I was able to analyze ~all the events that were taken.  Here's the summary of slopes vs. eta:

I've attached at the bottom of the page lists of slopes for individual towers.  The format is the same as before, although I've adjusted the chi2 cut to 300 because of the additional statistics and I've also adjusted the 4*RMS slope cut to take into account the updated mean and RMS values from the plot above.

Third Iteration

Data gathered from runs 8090021, 8090022, 8090023.  The only change I made to the code was to tweak the parameters of the pedestal fit a little bit, since I noticed a couple of towers where it failed.

Fourth Iteration

Data gathered from Runs 8091003, 8091005, 8091007.  Same analysis codes as in Third Iteration

Fifth Iteration

Runs:  8092080, 8092081, 8092083

Seventh Iteration

Run 8095073, 600k events.

This summary plot highlights swapped towers in red.  As Steve pointed out, we weren't adjusting the HV of these tubes correctly in most of the previous iterations.