General Meeting Summary 4/4/19

MAGNET (Charles, Bogdan, Rolf)

• Assembly and testing (Charles)

• Good progress with setting up for mapping tests, working on modifications for mounting the traveling stage
• OSP in progress - expect first draft on 4/8

• NPS Fringe Fields (Bogdan, Rolf)

• Discussion of slides

• Results show that a minor (mm-scale) vertical offset that can be taken into account in HMS optics as is standard practice
• Further mitigation of the already small vertical offset can be achieved with shielding; in this case no optics correction is needed
• Horizontal offsets are negligible

PMT AND DIVIDERS (Vladimir, Alex S.)

• Crytur crystals and modified/bypassed bases have been tested and installed in 3x3 prototype. Plan to install the prototype behind the pair spectrometer in Hall D on 4/8.
• Reduced gain (4-6 compared to 28) amplifiers are being prepared
• Anticipate some test time for modified amplifiers also with NPS prototype/ComCal at end of spring run

CRYSTALS (Vladimir, Tanja)

• Discussion of dimension comparison Crytur vs. SICCAS - both vendors were originally given specs: 20.5 +0.05/-0.05mm

• SICCAS mean globally higher than specs - would be consistent with 20.6 +0/-0.1mm
• CRYTUR mean is ~20.45mm, which is consistent with vendor requested and approved modified specs 20.5 +0/-0.1mm
• Crystal-to-crystal size variation is +/-0.05mm for Crytur and large fraction of SICCAS crystals, in particular the first 460 pieces
• Variation in size along the crystal for Crytur is 0.025mm

• REJECTION CRITERION: crystals will be rejected if larger than 20.6mm

• Optics tests of the 160 replacements SICCAS crystals are ongoing. Many fail light yield requirements.

FRAME (Carlos)

• Mock-up tests ongoing - identified issues with PCB board sliding and working on solutions

• Work on cable dimensions ongoing

• Mechanical calculations for carbon fiber structure supporting crystals ongoing - expect deformation on order 5-6um

SOFTWARE (Ho San)

• Adapting Hall A clustering/photon detection analysis software to NPS configuration

• Thinking of ways to expedite NPS analysis compared to Hall A? - e.g. better algorithms, higher speed

• Online data taking also important - Brad S is working on this

ERR PREPARATIONS

• Next meeting (4/18) will start with discussion of the speakers' rough content presentation slides - please prepare slide titles, table of contents or equivalent
• 4/18 meeting will be two hours

TCS UPDATE (Vardan)

• Presentation of ongoing simulation studies and results

NEXT MEETING: THURSDAY 18 APRIL 9:00-11:00 AM (ET)