[Halld] DIRC commissioning summary

[Justin Stevens]

Hi All,

These past ~11 days we’ve collected more than 10 billion events with the DIRC to calibrate and commission half of the detector.  As Bill reported, there were issues identified with the firmware that were solved and allowed us to run at rates quite close to the planned High Intensity GlueX-II conditions this coming Fall.  Initial calibrations are in place, and the data look quite reasonable in our first pass of analysis.  There is still plenty of work (and data analysis) to be done, but initial indications are that we’ve collected the data needed to satisfy the goals of this commissioning period (you’ll hear more at the Collaboration Meeting this week).

Thanks to the Hall D staff and technical groups for all their efforts to make this commissioning possible during the short installation and commissioning window we had this Spring.  And I would like to express my personal thanks to the on-site DIRC team (Bill, Andrew, Joe, Roman, Yunjie, Maria, Greg, Matt, et al.) that has worked tirelessly these last few weeks to ensure we collected a high quality dataset with as many systematic checks as possible.

For some fun visualization of how our Cherenkov rings develop in the DIRC you can checkout this animated GIF showing one example hit pattern from data collected last week:
https://halldweb.jlab.org/wiki/images/c/cd/PixelHit3D_Pi%2B_Bar7_xbin19.gif

On behalf of the DIRC team,
Justin