January 21, 2014

Meeting Time and Place

Tuesday January 21, 2014 at 1:30pm

Connections

To connect from the outside, please use ESNET or SeeVogh

1. ) ESNET: 8542553
   
2. ) SeeVogh: A conference has been booked under "GlueX Trigger Working Group" from 1:00pm until 3:00pm (EDT).
   1. ) To phone into an SeeVogh meeting, from the U.S. call (626) 395-2112 and then enter the EVO meeting code, 159726.
   2. ) To use the SeeVogh Java script use the SeeVogh link.

Agenda

1. Announcements
   • Collaboration Meeting
2. Tagging calibration data "streams" in Level-3
   • Recommendations from software review report:
     1. We recommend the inclusion of calibration in the data challenges. Demonstration of a functional prompt calibration loop will be an important element of achieving rapid extraction of physics results.
     2. Event tagging in the HLT is recommended as a mechanism for separating calibration data samples into streams for use in a prompt calibration loop.
   • Requesting feedback from detector groups on what calibration data samples might be useful
3. Level-3 Trigger Update

Minutes

1. Collaboration Meeting
   • The tentative schedule is to have three talks from Chris (Trigger Electronics), Alex (L1), and Justin (L3)
2. Tagging calibration data "streams" in Level-3
   • As discussed in the calibration meeting, the detector groups are requested to start compiling a list of the types of data samples that would be useful for calibration
     • Curtis suggested a presentation on what other experiments do (eg. LHCb) would be useful
   • In terms of implementation we discussed a couple of options:
     1. Setting a flag in the data stream for events which would be useful for calibration
     2. Writing events useful for calibration to separate data files (which could be processed quickly by calibrators online, if desired)
   • From previous discussions with the DAQ group it seems that writing events to multiple streams is possible, but it hasn't been done previously.
   • For the spring online data challenge, the plan will be to implement the event flagging in the data stream and postpone the writing of events to separate streams until later
3. Level-3 Trigger Update
   • Justin presented an update on the L3 algorithm by improving the track momentum resolution using wire-based tracking
     • The track momentum resolution is dramatically improved with wire-based tracking for polar angles < 15 degrees
     • The momentum resolution is noticeably worse for tracks in the CDC with DTrackWireBased relative to DTrackCandidates which has been seen before (by Simon) and is unexpected and not understood
   • Using wire-based tracking for this subset of the track candidates will moderately increase in CPU time while improving the performance of the trigger to ~95% efficiency
   • The plan is to test this algorithm on the online nodes in the counting house to get better estimates of CPU performance for different tracking options and BDT staging