Difference between revisions of "Minutes-5-7-2015"

From GlueXWiki
Jump to: navigation, search
Line 17: Line 17:
 
# Engineering
 
# Engineering
 
# Other
 
# Other
 
<!--
 
  
 
= Minutes =
 
= Minutes =
Line 26: Line 24:
 
== Gas puzzle ==
 
== Gas puzzle ==
  
- Last CO2 results linked above. CDC percentage was stable during the run at ~52-53% level. After the end of the run the sensor was moved to the tagger hall and connected to the spare package with 40% CO2, but it was showing 37-38%.
+
- Last CO2 results linked above. CDC percentage was stable during the run at ~52-53% level. After the end of the run the sensor was moved to the tagger hall and connected to the spare package with 40% CO2, but it was showing 37-38%.  
  
 
== CDC update ==
 
== CDC update ==
  
- Mike: CDC is working fine. One HV channel (G14) is not stable, most likely problem in the CAEN module.
+
- Mike showed results from the spring run for the CDC efficiencies (linked above) as function of distance to the wire and path length. Compared to the fall run and taken into account that the lower gain (due to the gas having more CO2) there's effectively increase in the efficiency thanks to the HV filter boxes. Two HV card showed some problems at the end of the run; Mike will look at this.
  
 
== FDC update ==
 
== FDC update ==
  
- First look at the FDC efficiency now with 6.3V threshold on the discriminators. Compared to the 8V thresholds (on the picture attached: black 6.3V, red 8V from previous run) before we see just a little increase of the efficiency from 94 to about 95%: not significant; could also be noise.
+
- Lubomir compared the efficiencies from the fall and spring run, the latter with two HV settings 2200 and 2250, there's no visible change in the efficiency meaning no need to work at 2250V.
 
+
== Electronics ==
+
 
+
- The power supply of a NIM crate in EEL126 used in the make a cosmic trigger failed; people there smelled it burning. The crate was labeled. Nick and Chris will look into this, and possibly replace the power supply.
+
 
+
== Other ==
+
 
+
- Tests with the spare package in the tagger. The chambers see high rates from: 1)background photons over the whole sensitive area and 2) electrons from the radiator in the shear plane of the magnet of the order of 100kHz per wire. Electrons, unlike photons, make hits in the two chambers of the spare package, that's how they are separated.
+

Revision as of 14:57, 15 May 2015

May 7, 2015 FDC+CDC meeting

Connection

  1. Instructions for Bluejeans meeting connection
  2. FDC meeting ID: 290664653
  3. To join via a Web Browser, go to the page [1] https://bluejeans.com/290664653.

Agenda

  1. Gas puzzle
    • CO2 monitoring [2]
  2. CDC update (Beni, Mike)File:CDCEfficiencyUpdate7May.pdf
  3. FDC update (Lubomir)
  4. Electronics (Fernando, Cody, Chris, Nick)
  5. Engineering
  6. Other

Minutes

Participants: Curtis, Naomi (CMU), Sean (NU), Luke, Fernando, Mike, Dave, Chris, Nick, Simon, and Lubomir (JLab).

Gas puzzle

- Last CO2 results linked above. CDC percentage was stable during the run at ~52-53% level. After the end of the run the sensor was moved to the tagger hall and connected to the spare package with 40% CO2, but it was showing 37-38%.

CDC update

- Mike showed results from the spring run for the CDC efficiencies (linked above) as function of distance to the wire and path length. Compared to the fall run and taken into account that the lower gain (due to the gas having more CO2) there's effectively increase in the efficiency thanks to the HV filter boxes. Two HV card showed some problems at the end of the run; Mike will look at this.

FDC update

- Lubomir compared the efficiencies from the fall and spring run, the latter with two HV settings 2200 and 2250, there's no visible change in the efficiency meaning no need to work at 2250V.