Difference between revisions of "Meeting 1/27/22 - COMTRA"
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| − | ==Eric' | + | == Schedule == |
| + | * Joe reviewed schedule again, beam test window is shorter at UITF, now from Jun 1 - Oct 31, see slide 4 [[media:220127_COMTRA.pptx]] | ||
| + | |||
| + | ==ME layout== | ||
| + | |||
| + | * Joe proposed moving polarimeter test to non-dispersive "straight" section to avoid any energy dependent position jitter | ||
| + | * Shaun showed UITF beam line, identified how we could remove single spool in 4' pass-through, leaving irradiation line intact | ||
| + | * Joe is confirming this with Matt as first priority location | ||
| + | * Riad showed model/pics of ceramic break & radiator we'd like to use, 6mm thick copper, 1" flat surface for beam, approved for 10 MeV/100uA with cooling | ||
| + | * Riad will discuss with Eric if 6mm okay - then we move to fabricate second ceramic break & radiator | ||
| + | |||
| + | ==DAQ Procurement List - Chris and Riad== | ||
| + | |||
| + | * List of components needed to build two portable DAQ systems: [[media:ComptonTransPol_DAQ_PurchaseNeeds_2022Jan.xlsx]] | ||
| + | * Discussed possibility of running local EPICS, to provide convenient controls to DAC, PS, Helicity Board....Riad will discuss/confirm path forward | ||
| + | |||
| + | ==Polarized Target== | ||
| + | * Lakshmi will review the overall plan, when ready small group will meet to begin reviewing her questions about function and requirements | ||
| + | |||
| + | ==Simulation== | ||
| + | * Greg has installed Geant4 and loaded files to run some of the examples | ||
| + | * Greg would next like to learn to run and interpret output from the model Ben & Eric developed, then can add the radiator we'll use | ||
| + | |||
| + | ==Detector update - Eric== | ||
* I am in contact with the Alpha-Spectra company which was providing BGO crystals for a local project we had in Orsay. This is a US company which provides crystals with a guaranteed 8-9% resolution. At the time we were investigating for an order they were less expensive than Saint-Gobain and turned-out to be more performant (we performed dedicated measurements to test this). | * I am in contact with the Alpha-Spectra company which was providing BGO crystals for a local project we had in Orsay. This is a US company which provides crystals with a guaranteed 8-9% resolution. At the time we were investigating for an order they were less expensive than Saint-Gobain and turned-out to be more performant (we performed dedicated measurements to test this). | ||
| Line 6: | Line 29: | ||
* It should be noted that litterature about radiation aging of BGO crystals indicates that after a rapid loss of about 20% of transmission, the performance is kind of stable. Some experiments chose to first irradiate crystals to operate in that regime. | * It should be noted that litterature about radiation aging of BGO crystals indicates that after a rapid loss of about 20% of transmission, the performance is kind of stable. Some experiments chose to first irradiate crystals to operate in that regime. | ||
| − | * | + | * We may need tools to control the overall stability of the experimental signal... dedicated cosmic ray calibration run or light illumination... too early stage to provide a direction of answer, but this should be kept in mind. |
Latest revision as of 11:43, 27 January 2022
Schedule
- Joe reviewed schedule again, beam test window is shorter at UITF, now from Jun 1 - Oct 31, see slide 4 media:220127_COMTRA.pptx
ME layout
- Joe proposed moving polarimeter test to non-dispersive "straight" section to avoid any energy dependent position jitter
- Shaun showed UITF beam line, identified how we could remove single spool in 4' pass-through, leaving irradiation line intact
- Joe is confirming this with Matt as first priority location
- Riad showed model/pics of ceramic break & radiator we'd like to use, 6mm thick copper, 1" flat surface for beam, approved for 10 MeV/100uA with cooling
- Riad will discuss with Eric if 6mm okay - then we move to fabricate second ceramic break & radiator
DAQ Procurement List - Chris and Riad
- List of components needed to build two portable DAQ systems: media:ComptonTransPol_DAQ_PurchaseNeeds_2022Jan.xlsx
- Discussed possibility of running local EPICS, to provide convenient controls to DAC, PS, Helicity Board....Riad will discuss/confirm path forward
Polarized Target
- Lakshmi will review the overall plan, when ready small group will meet to begin reviewing her questions about function and requirements
Simulation
- Greg has installed Geant4 and loaded files to run some of the examples
- Greg would next like to learn to run and interpret output from the model Ben & Eric developed, then can add the radiator we'll use
Detector update - Eric
- I am in contact with the Alpha-Spectra company which was providing BGO crystals for a local project we had in Orsay. This is a US company which provides crystals with a guaranteed 8-9% resolution. At the time we were investigating for an order they were less expensive than Saint-Gobain and turned-out to be more performant (we performed dedicated measurements to test this).
- They should be back to me shortly with information about availability of improved radiation hardness crystals as well as radiation limits of the crystals they are currently providing.
- It should be noted that litterature about radiation aging of BGO crystals indicates that after a rapid loss of about 20% of transmission, the performance is kind of stable. Some experiments chose to first irradiate crystals to operate in that regime.
- We may need tools to control the overall stability of the experimental signal... dedicated cosmic ray calibration run or light illumination... too early stage to provide a direction of answer, but this should be kept in mind.