Difference between revisions of "Meeting-6-29-2017"

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#* TRD (Lubomir)
 
#* TRD (Lubomir)
  
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= Minutes =
 
= Minutes =
  
Participants: Curtis, Mike, Naomi (CMU) Sean (NU) Alexander A., Beni, Chris, Simon, Sergey, and Lubomir (JLab).
+
Participants: Curtis, Mike, Naomi (CMU) Alexander A., Beni, Chris, Simon, Sergey, and Lubomir (JLab).
  
 
== CDC ==
 
== CDC ==
  
 
- We discussed briefly the effect of the space charge on the dE/dx in the CDC (as reported on the analysis meeting). This is a project that requires fitting of the dE/dx angular dependence for different particles (electrons, pions, kaons, protons) and correcting for it, which will significantly improve the PID. Sergey: the effect will depend also on the CDC HV. Curtis proposed to contact Klaus Peters and Nacer (GSI) since they were interested in the dE/dx studies.
 
- We discussed briefly the effect of the space charge on the dE/dx in the CDC (as reported on the analysis meeting). This is a project that requires fitting of the dE/dx angular dependence for different particles (electrons, pions, kaons, protons) and correcting for it, which will significantly improve the PID. Sergey: the effect will depend also on the CDC HV. Curtis proposed to contact Klaus Peters and Nacer (GSI) since they were interested in the dE/dx studies.
- Chris: the CDC cables were disconnected and re-routed (by Nick) to have more slack and better access to the electronics.
 
- Fernando and Lubomir studied the noise in the Hall related to high trigger rates. The noise is seen on the FDC TDCs coming from the input to the discriminators. Scope screen - yellow is the trigger at the SD, pink is the discriminator output. On the spectral analyzer the noise had equidistant peaks - ~3.3 MHz apart for 60 kHz trigger rate and ~10 MHz apart for 15 kHz trigger rate - with an amplitude ~10dB in a wide range of 100MHz. The noise is seen everywhere on the crates and also along the signal cables. Fernando: the noise is low, but maybe combined from all the crates might indues measurable signals on the wires (Lubomir), as is the case. Discussions with Sergey after the meeting - the data rates (due to the noise) on some TDC crates are very high limiting the DAQ performance for the high intensity running.     
 
  
== Tracking ==
+
- Chris: the CDC cables were disconnected and re-routed (by Nick) to have more slack and better access to the electronics. Once cables are re-connected Nick will test them with the f125 pulsers. Naomi will contact Nick about a few channels with lower gain to be tested.
  
- Mike reported on his plan for the CDC and FDC alignment (see the link above). On a scale of +/- 250 microns one certainly sees in the FDC residuals some non-uniform features over the area of the chambers. The residuals are from a run with magnetic field and tracking through both CDC and FDC without excluding the corresponding chamber from the track. The plan is to use MILLEPED but before that it requires some good work: fix some issues with the output from the Kalman filter, calculate full co-variance matrix (not only diagonal elements), implement straight line tracking through both CDC and FDC, standardize the geometry and alignment constants.
+
== FDC ==
  
- Sean discussed a plan to improve the tracking simulations (linked). This includes two steps: update the detector hit objects, then study the performance of reconstructed tracks.  
+
- Alex A. pointed again on the pattern seen in the FDC efficiency, reported also yesterday on the analysis meeting. It may come from the inefficiency in the field wire region, but to have this effect the track has to pass through this region in all the chambers (four required) in the same package. Simon and Alex will further investigate this.
  
== Other ==
+
- Fernando submitted a PR for additional LV modules and a chassis to improve the FDC threshold segmentation by a factor of 4 - will have one threshold per chamber. A new distribution box is need, as well, and Nick was working on it.   
  
- Next meeting in two weeks
+
== Tracking ==
 +
 
 +
- Mike is done with the alignment improvements. Curtis: Alex Barnes will be joining the CMU team and will continue with the alignment studies.
 +
 
 +
== Other ==
  
-->
+
- TRD: two modifications will be made on the TRD prototype for the fall run. The drift gap will be increased from 2 to 3.2cm and the entrance window will be replaced with a thinner material - chromium foil.

Revision as of 17:19, 29 June 2017

June 29, 2017 Drift Chamber meeting

Connection

  1. Instructions for Bluejeans meeting connection
  2. Meeting ID: 290664653

Headline text

  1. To join via a Web Browser, go to the page [1] https://bluejeans.com/290664653.

Agenda

  1. CDC
  2. FDC
  3. Tracking
    • Alignment progress? (Mike)
  4. 2017 mcsmear Workplan
  5. fADC125? (Naomi, Cody, Beni)
  6. Other
    • TRD (Lubomir)


Minutes

Participants: Curtis, Mike, Naomi (CMU) Alexander A., Beni, Chris, Simon, Sergey, and Lubomir (JLab).

CDC

- We discussed briefly the effect of the space charge on the dE/dx in the CDC (as reported on the analysis meeting). This is a project that requires fitting of the dE/dx angular dependence for different particles (electrons, pions, kaons, protons) and correcting for it, which will significantly improve the PID. Sergey: the effect will depend also on the CDC HV. Curtis proposed to contact Klaus Peters and Nacer (GSI) since they were interested in the dE/dx studies.

- Chris: the CDC cables were disconnected and re-routed (by Nick) to have more slack and better access to the electronics. Once cables are re-connected Nick will test them with the f125 pulsers. Naomi will contact Nick about a few channels with lower gain to be tested.

FDC

- Alex A. pointed again on the pattern seen in the FDC efficiency, reported also yesterday on the analysis meeting. It may come from the inefficiency in the field wire region, but to have this effect the track has to pass through this region in all the chambers (four required) in the same package. Simon and Alex will further investigate this.

- Fernando submitted a PR for additional LV modules and a chassis to improve the FDC threshold segmentation by a factor of 4 - will have one threshold per chamber. A new distribution box is need, as well, and Nick was working on it.

Tracking

- Mike is done with the alignment improvements. Curtis: Alex Barnes will be joining the CMU team and will continue with the alignment studies.

Other

- TRD: two modifications will be made on the TRD prototype for the fall run. The drift gap will be increased from 2 to 3.2cm and the entrance window will be replaced with a thinner material - chromium foil.