last update 050131
STAR Trigger Startup Plan
For details and status, see startrup plan.
Before we can use the trigger reliably we need to establish the correct timing with respect to the RHIC clock and determine the characteristics of min bias events.
STEP 1: Time the Trigger Strobe
Check RHIC Clock stability
Check ADC gate timing. This can be done by checking the ZDC height as a function of RHIC strobe delay, enterred via the V124 input panel in the RHIC workstation. We can time the BBCs, CTBs and ZDCs independently, although we have tried to arrange their cabling so that they will fall within a common gate time.
Check BRB and YRB timing. This can be accomplished with a simple scan of the fill pattern for the two rings, to determine which bucket is in synch with the CTB trigger.
Make sure all the detector info is in each event. We can check this by triggering on a coincidence between the ZDCE and ZDCW and runing a pre-post of 5 to see which RS the CTB info falls into.
STEP 2: Take 10-100k min bias events
STEP 3: Check uniformity of CTB response using p>1 GeV/c tracks, single hits per slat
STEP 4: Correlate CTB with ZDC
Check ZDC signals as a function of CTB multiplicity
STEP 5: Agree on beam-gas elimination cuts
STEP 6: Agree on definitions of CENTRAL, PERIPHERAL, and trigger mix
With physics committee and Collaboration
STEP 7: Take test runs for each type and for mix
Establish baseline plots for comparisons
Check lifetimes of beams
STEP 8-...: RUN
Once we are running on BBC, ZDC and CTB triggers, we begin to evaluate thecalorimeters as trigger detectors.