Scaler analysis

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Scalers allow to count durinng the run, they are used for normalization and counting.

The scalers are located on both arm on in the VME trigger superviser crates.

They are readout in the data every 100 events.

They are also inserted asynchronoulsy.

The end of run files record the scalers at the end of the run.

One use of these file by Robert Michaels to check the rate stability.

Entry number 199844 keyword=trig. stability check (good)

I checked the trigger stability, before and after the Open House since we're running the same kinematics. See fig 1. It looks pretty stable. This plot was made with the root macro "tstab.C". On adaq, type "goxscaler", the macro is there (see the macro for instructions) -- an example of how to check scaler run histories.

The scaler display is accessible in the adaq account : goxscaler ./xscaler

The description of the display and scaler channels is recoded in