Thursday, February 27, 2014 2:30pm EST - Compton
From Hall A Wiki
Previous meeting: Tuesday, December 10, 2013 11am EST - Compton
Tentative Agenda
- Updates
- laser (Kent)
- DAQ (Bob/Alex)
- photon detector (Greg/Vahe)
- electron detector (Juliette/Dipangkar)
- magnetic field mapping (Kent)
- beamline status/accelerator schedule (Alex)
- consequences of restructuring (Dave/Thia)
- Next meeting time
Minutes
Attending: Juliette, Dustin, Dave, Alex, Brian, Greg, Kent
- Updates - Near term and long term goals, mostly near term (DVCS, PREX/CREX)
- laser (Kent/Dave)
- near term - getting running again (how it was set up before)
- few kW green power (easier then IR)
- green good for PREX
- work in hall (not in laser lab - 2nd floor ARC)
- Chuck Long (spectrometer group - Jack Segal running)
- single-pass frequency doubling only problem (expertise at the lab)
- still trying to locate parts - crystal (several purchased)
- thermoelectric chillers to control temp
- stage still on table
- Abdurahim - thesis - photos, etc.
- trying to organize after restructuring
- Just photon okay for DVCS (don't want to break anything :))
- actuators for optics (after laser is running)
- with 12 GeV, green won't fit in beampipe at 12 GeV - redesign e- det can
- small slot - French connection? - redesigned?
- last real-world experience - power 5kW? - mirrors degrade in tunnel
- DAQ (Bob/Alex)
- put computer back in counting house
- trying to run the flash ADC DAQ on it
- High flip rate capability of the DAQ (MOLLER)
- old DAQ - ran at 30 Hz
- trigger supervisor, event triggered DAQ
- PREX won't use e- det - flash ADC with photon det
- photon detector (Greg/Brian)
- existing GSO brought back to CMU
- modified so it will fit
- more adjustability - need some safety stops on xy table
- eventual plan - two detectors one for higher energy
- analyzing power factor of 2 with green laser
- with GSO photon energy is not as much of a factor
- photon used for DVCS
- looking at PbW for 12 GeV
- no timeline
- Sirish had a source for large crystal - Shanghai?
- 2cm square are common - wrap them together... if no choice
- 3% would be pretty useful for DVCS
- Hall C four crystals will fit (but not the box they're in)
- cooling PbW
- light output fluctuates near room temp.
- more light with cooler - 15 C?
- need to calibrate with spectrum in counting, and would be distorted
- if energy changes, then effects from that, too
- radiation level too high for lead glass? (1 MHz photon rate)
- better for lead flouride (3x3cmsq, 18.6 cm long?)
- for near term - 4 crystal lead tunsgate in DVCS with and without cooling
- existing GSO brought back to CMU
- electron detector (Juliette/Alex)
- MOU completed
- Alex preparing contract to loan
- single plane w/half not functional
- French A/D
- QWAD
- analog amplifier board (is this the ARS16?)
- plan to try to get a postdoc for Compton work/PREX
- magnetic field mapping (Kent)
- beamline status/accelerator schedule (Alex)
- upcoming beam test in March
- DVCS in the fall
- 12 GeV halo bigger
- Synchrotron light at 12 GeV running
- laser (Kent/Dave)
- consequences of restructuring
- next meeting time
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