Meeting 2022 07 27
From Hall A Wiki
GMn GEM commissioning Meetings: WEDNESDAY 10:30am - 11:30am
Link to all previous meetings: GMn GEM Commissioning Meeting
Please use sbs_gems mailing list for plots/communications and HALOG entries relevant to GEMs!
Near term work plan
- We found long BNC cables from the physics storage and routed them so that we have a clock and trigger signals to start doing the low level tests as soon as the creates are on the network.
- Also we are still waiting for the order of BNC cables.
- Long fiber cable was routed and Armen/Mark from the electronics group will install the fiber patch panes today.
- We will route network cables to all the crates/power strips today and then get all the crates on the network.
- Jack is working on supplying power to the SBS GEM bunker.
- Once all of the above steps are completed, we can start doing the low level test to debug cable connections and set clock-phase and other parameters correctly. Hopefully can be started later this week.
- See installation plan for SBS here: plan
- [photos from the hall https://hallaweb.jlab.org/wiki/index.php/File:Installation_Update_22June2022.pdf]
- Installation of HV dividers on BB: work plan
- Thoughts on special run requests during GEn:
- Luminosity studies (Nilanga)
- Full readout studies for negative pulse studies and etc (Sean)
Update on INFN GEM layers for GEn-RP
- Ran up a new divider on the front layer GEM of the inline stack. Verified temperature and V/I consistent with divider run-up with no GEM.
- Currently in Hall. Plan to install new dividers on upstream-most layer while we can easily access. Will need sliding platform to remove the layer to install the new dividers on the second layer.
Update on UVa GEM layers for GEn-RP
- UVA GEM HDMI, HV and LV cables are all connected both from the detector side and crate sides.
- The order of gas sut-off valves arrived and we have connected them and start flushing the GEMs with Nitrogen since Monday.
- Plan to do a HV test on UVA GEMs sometime early next week.
Update on BB GEMs
- Cosmic data analyzed from last week, https://logbooks.jlab.org/entry/4017798
- All modules with new dividers look good.
- Some replaced APVs are still giving dead areas, which cannot be fixed, but are <5% of the total active area.
- One XY module is very low efficiency, but the gain looks normal. I am investigating if this is a tracking issue.