Responses to Shelly's 7 questions for the trigger scintillator and electronics:
1) Briefly review the current status of your system: is it a)
assembled b) tested c) ready for shipping ? If not, what are
the remaining critical milestones and how will your group meet
them?
- Scintillator 1: a,b, and c are done.
- Scintillator 2: c is done, a and b will be completed shortly. We need to attach the PMTs and test the response, which should take about one week unless there is something wrong with the scintillator.
- Meantimer: still needs to be tested. The steps to take have been worked out with Paul and we estimate that it will take about 2 weeks to get the meantimer working with our current DAQ and then about 1 month to get it working with CODA.
2) Briefly summarize the installation and integration issues when your system is installed at JLab. How will these be addressed?
- The scintillators will be mounted to the region 3 chambers so will be installed with region 3. Mounting of the region 3 chambers and the trigger scintillators has to be adjusted to center the beam envelope on the active areas.
- The trigger scintillator and DAQ will be set up in the EEL this summer so that subsystems can test their pieces with the trigger DAQ before installation.
3) Describe the tests to be made with beam during the commissioning phase for your system. What analysis tasks will need to be done to confirm that it is ready for production mode?
We should look at the scintillator response at low beam current. Then, go up to higher beam currents and see what the limitations are such that the trigger dead time is less than 10%.
4) Briefly summarize the nature of the analysis software needed for your system and its current status. Who is in charge of this software for your group?
Katherine is in charge of the analysis software. For the scintillators, all that needs to be done is calculate the position of the hit from the L-R signal. With the current DAQ setup on scintillator 1 we have shown that our position resolution is about 0.5 cm and our timing resolution is about 750 ps.
5) Who is in charge of documentation (both hardware and software) for your system? How will general shift workers be trained to operate it?
Katherine is in charge of the documentation related to the scintillators. It should be fairly simple for other people to learn. Documentation for the trigger electronics will be written by Katherine and Paul. For the commissioning phase, we suggest an expert be on shift 24/7 so other shift workers will not need to be trained on the trigger electronics. By the time we get to production mode we should have a number of event triggers available for shift workers. Changing between event triggers will be straightforward and documentation will be provided by Katherine. These will probably be:
- A=L.AND.R of a single trigger scintillator
- A.AND.(correlated quartz bar)
- A.AND.scanner
- A.AND.(some minimum number of hits in region 3 chambers) [software]
- A.AND.?
6) List the members of the team dedicated to installing, commissioning and running your system for Qweak. Indicate a schedule for who you plan to have at JLab and when.
Katherine and Allena are in charge of installing and commissioning the trigger scintillators. Katherine will be at JLab full-time and Allena about 7 days/month.
7) Does your system require a dedicated expert on each shift? Do you need to recruit additional manpower from the collaboration at large?
No dedicated persons are required for the trigger scintillators. However, we suggest a decidated trigger electronics expert be on shift 24/7 during the commissioning phase. These experts will be Paul, Katherine, Allena, a to-be-hired OU postdoc, and possibly some OU graduate students. Katherine will be at JLab full-time, Paul full-time, Allena about 7 days/month, and the postdoc would be here full-time.