July 2, 2014 Calibration

GlueX Calibration Meeting
Wednesday, July 2, 2014
11:00 am, EDT
JLab: CEBAF Center, F326

Connection Using Bluejeans

1. To join via Polycom room system go to the IP Address: 199.48.152.152 (bjn.vc) and enter the meeting ID: 630804895.
2. To join via a Web Browser, go to the page [1] https://bluejeans.com/630804895.
3. To join via phone, use one of the following numbers and the Conference ID: 630804895
   • US or Canada: +1 408 740 7256 or
   • US or Canada: +1 888 240 2560
4. More information on connecting to bluejeans is available.

Agenda

1. Announcements
2. Status Update
   • Constants_to_Review
3. Tracking
   • Cosmics Running
   • CDC radial field drift-time diffs
   • CDC drift-time & B field doc
4. Calorimetry
5. Other systems
6. Simulations and Calibrations

Minutes

1. Announcements
   • Mark I. has tagged CCDB v1.02. This primarily fixes bugs related to when a primary variation for a JANA program is specified on the command line (e.g. JANA_CALIB_CONTEXT="variation=mc").
2. Tracking
   • Naomi put together this document which describes her investigations on correcting for B-field variations. She also redid her studies of radial B-field variation with finer resolution and found a maximum difference of 3 ns at maximum drift time.
   • The current time-to-distance tables for the CDC are generated assuming a magnetic field. Simon is being provided with tables corresponding to zero magnetic field. It was noted that the gas mixture in the CDC has a temperature around 296K.
   • There was also a
3. Calorimetry
   • Zisis (via email) reported on a discussion during the BCAL Commissioning meeting. The current plan to to have the Regina students at JLab begin analyzing the BCAL LED pulser & cosmic data that they are taking, under the supervision of Elton and Mark D. These data will be compared against the standard HDGeant simulations, and a standalone BCAL simulation which contains a more detailed geometry.
4. Other systems
   • Richard J. (via email) has put constants in the CCDB for the energy ranges that correspond to hits in the tagger microscope & fixed array, based on an analysis by Dan Sober. He is updating the simulation to use these values.
5. Simulations, etc.
   • Mark I. reminded us that we should be using different variations as we update the values of constants, e.g., if they correspond to calibrations for data or MC.