Difference between revisions of "General Meeting Summary 3/7/19"
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(Created page with "MAGNET (Charles, Bogdan) * Safety and Operations documents ::* OSP for mapping is being prepared - expected to be complete in week 3/11 ::* More detailed documents needed for...") |
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* Best solutions for NPS HV dividers seems to either bypass amplifier or to reduce the amplification - both are practically easy to do | * Best solutions for NPS HV dividers seems to either bypass amplifier or to reduce the amplification - both are practically easy to do | ||
| − | ::* slight preference to bypass the amplifier | + | ::* slight preference to bypass the amplifier - 100uA is average anode current, peak anode current is 100mA/pulse, so have some dynamic range available --> bypass should be ok |
| + | ::* practically bypass means directly connect signal to output | ||
* Planned tests with sample dividers with bypassed amplifier and reduced amplification | * Planned tests with sample dividers with bypassed amplifier and reduced amplification | ||
| + | ::* idea: compare gains (e.g. 1=bypass, 2=...) and rates and choose best option experimentally | ||
::* test with beam in Hall D | ::* test with beam in Hall D | ||
::* test bench either after or instead of beam tests - expect to put all together in lab in 2-3 weeks | ::* test bench either after or instead of beam tests - expect to put all together in lab in 2-3 weeks | ||
| + | |||
| + | * Planned test with 3x3 prototype and Crytur crystals | ||
| + | ::* idea: test dependence of saturation on crystals (SICCAS vs. Crytur) | ||
| + | ::* space and opportunity in Hall D | ||
* A few notes on PMT, divider, and fADC | * A few notes on PMT, divider, and fADC | ||
| Line 46: | Line 52: | ||
::* fADC dynamic range for earlier 3x3 prototype tests was 1 V | ::* fADC dynamic range for earlier 3x3 prototype tests was 1 V | ||
::* ComCal/NPS prototype has different crystals than the 3x3 prototype | ::* ComCal/NPS prototype has different crystals than the 3x3 prototype | ||
| + | ::* For original HV divider design assumed 8 pe/MeV light output | ||
Latest revision as of 12:25, 19 March 2019
MAGNET (Charles, Bogdan)
- Safety and Operations documents
- OSP for mapping is being prepared - expected to be complete in week 3/11
- More detailed documents needed for ERR
- Details of mapping plan for ERR
- Planning to bring mapper to JLab in week 3/11
- Fringe fields
- Additional calculations made for downstream of magnet with passive shielding - sent this information to Jay Benesch
- Action item: redo calculations of front of HMS (snout) for ERR - this is relevant for the optics
- Paulo redid distances
- need set of kinematic positions
- Action item: determine sensitivity of experiments to up/down asymmetry due to magnetic field
- magnet horizontal field changes up/down position of detector - for measurements only matters if sensitive to up/down asymmetry
- DVCS measures up/down - need to think about and have answer for ERR
- Is the power supply reversible? - need to include in ERR
FRAME AND SIMULATIONS (Carlos, Ho San)
- Working on full prototype for tests of movable boards for PMT access
- Deciding on cable lengths and work distribution
- clarifying quotes and prices, e.g. labor and part per cable
- Testing fibers
HV DIVIDERS (Vladimir, Alex S., Fernando)
- Discussion of recent ComCal/NPS prototype results
- Best solutions for NPS HV dividers seems to either bypass amplifier or to reduce the amplification - both are practically easy to do
- slight preference to bypass the amplifier - 100uA is average anode current, peak anode current is 100mA/pulse, so have some dynamic range available --> bypass should be ok
- practically bypass means directly connect signal to output
- Planned tests with sample dividers with bypassed amplifier and reduced amplification
- idea: compare gains (e.g. 1=bypass, 2=...) and rates and choose best option experimentally
- test with beam in Hall D
- test bench either after or instead of beam tests - expect to put all together in lab in 2-3 weeks
- Planned test with 3x3 prototype and Crytur crystals
- idea: test dependence of saturation on crystals (SICCAS vs. Crytur)
- space and opportunity in Hall D
- A few notes on PMT, divider, and fADC
- R4125 is rated for 1500 V operating voltage, maximum anode current is 100 uA
- fADC dynamic range for earlier 3x3 prototype tests was 1 V
- ComCal/NPS prototype has different crystals than the 3x3 prototype
- For original HV divider design assumed 8 pe/MeV light output
CRYSTALS (Vladimir, Tanja)
- Received 160 replacement crystals from SICCAS - inspection ongoing
- [http://www.vsl.cua.edu/cua_phy/index.php/MainPage:Nuclear:NPS:PWO:CrystalLOG#JLAB_160_replacement_pieces_.282019.29_Details Some results in section JLAB 160 replacement pieces (2019) Details
- In contact with Crytur about procurement of additional crystals
ERR PREPARATION
- Created Wiki page NPS ERR for people to start filling in
NEXT MEETING: THURSDAY 21 MARCH at 9:00 AM (ET)