Difference between revisions of "Minutes-7-14-2016"

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#* CDC update (Naomi/Mike/Beni)
 
#* CDC update (Naomi/Mike/Beni)
 
#* FDC update (Simon/Lubomir/Alex)  
 
#* FDC update (Simon/Lubomir/Alex)  
−
#**[[File:fdc_jul14_16.pdf]]
+
#**[https://halldweb.jlab.org/wiki/images/3/34/Fdc_jul14_16.pdf First look using standard fitting code using FDC drift times]
 +
#** Electron deflection in B field Garfield: [http://www.jlab.org/Hall-D/detector/fdc/garfield/garfield_2T_perp_RK.pdf perp. to wire],  [http://www.jlab.org/Hall-D/detector/fdc/garfield/garfield_2T_16deg_RK.pdf at 16deg.], [http://www.jlab.org/Hall-D/detector/fdc/garfield/garfield_2T_16deg_MC.pdf MC at 16deg.], [http://www.jlab.org/Hall-D/detector/fdc/genfit/deflection_11615.pdf genfit results]
 +
#** Drift time in B field [http://www.jlab.org/Hall-D/detector/fdc/genfit/time_to_distance_11615.pdf genfit results]
 +
#** Resolutions with genfit [http://www.jlab.org/Hall-D/detector/fdc/genfit/Pdistr_11615.pdf Momentum distributions],[http://www.jlab.org/Hall-D/detector/fdc/genfit/XY_res_Bfield.pdf vs momentum], [http://www.jlab.org/Hall-D/detector/fdc/genfit/wire_res_Bfield.pdf wire resolution]
 +
#** Some systematics: [http://www.jlab.org/Hall-D/detector/fdc/genfit/XY_residualX_11615.pdf], [http://www.jlab.org/Hall-D/detector/fdc/genfit/XY_residualY_11615.pdf]
 
# NIM Papers
 
# NIM Papers
 
#* svn ls https://halldsvn.jlab.org/repos/trunk/publications/GlueXCDC
 
#* svn ls https://halldsvn.jlab.org/repos/trunk/publications/GlueXCDC
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# fADC125 meeting (Naomi, Cody, Beni)
 
# fADC125 meeting (Naomi, Cody, Beni)
 
# Other
 
# Other
−
 
−
<!--
 
  
 
= Minutes =
 
= Minutes =
  
−
Participants: Sean (NU),Curtis, Naomi, Mike (CMU) Luke, Alexander A., Simon, Sergey, and Lubomir (JLab).
+
Participants: Sean (NU), Mike (CMU) Eugene, Cody, Luke, Beni, Alexander A., Simon, and Lubomir (JLab).
  
 
== CDC ==
 
== CDC ==
  
−
- Naomi is working on the gain calibration, Mike on the straw deformation effects and corresponding errors.  
+
- In the analyses meeting Mike reported already [https://halldweb.jlab.org/wiki/images/b/b5/MStaibCDCEfficiencyS16.pdf his studies] on the CDC efficiency.
 +
 
 +
- Beni: Nick and Chris are cleaning/replacing the CDC HVB that had some issues during the last run due to some dust on them. We discussed possible origins of this dust: coming from the cooling tubes, air, or sucked by the magnetic field.
 
   
 
   
 
== FDC ==
 
== FDC ==
  
−
- Alex continued his presentation (linked above) from the last meeting now showing the Y-residuals (along wire) as a function of the X-residuals (first plot), both measured w.r.t. avalanche (hit) position. Since the avalanche is always on the wire, the X-residuals represents the drift distance and the Y-residual the deflection of the drifting electron due to the magnetic field. The linear correlation (third plot) means that the deflection is simply proportional to the drift distance, with a slope also proportional to the magnetic field. Garfield simulations confirm this. The Y-residuals are about 200 microns (second plot).
+
- Simon showed first plots about implementing the drift time in the FDC tracking.
−
 
+
−
- Alex also worked on the FDC timing both from fADC125s and TDCs(next two plots). The drift time offset calibration has to be done for each run, since it may move.
+
−
 
+
−
- Lubomir is working with the GENFIT tracking package to study the FDC performance in magnetic field. The package uses Kalman fitter but also combined with the Deterministic Annealing Filter (DAF) that assigns  weights to the hits and thus can solve left/right ambiguity. The package is using the Event Viewer Environment (Eve) for ROOT that offers good control over the fitting track by track (see pictures attached above).  Lubomir is working so far with straight tracks but will continue with curved ones.
+
−
 
+
−
== Other ==
+
  
−
- There was a meeting (see link) with the detector group (Drew  Weisenberger and Brian Cross) for building a TRD prototype. The plan is to build a chamber similar to the spare FDC package used for the TRD prototyping but with only 24x12 cm active area. The main difference is that we will apply negative HV to the upstream cathode that will be made out of thin aluminized Kapton.
+
- Lubomir studied the magnetic field effects with Garfield and showed that the effect of the avalanche deflection along the wire is equivalent to a wire rotation (of about 10deg for our field) w.r.t. avalanche position. The effect on the time-to-distance relation is equivalent to about 10% increase in the time scale.  
  
−
-->
+
- Lubomir showed GENFIT results about the FDC resolution in magnetic field (all results so far presented were without magnetic field): there's strong dependence on momentum and is better than 200 microns at high momenta. There's more work needed on the alignment as seen from some systematics in the residuals shown above.

Latest revision as of 19:36, 18 November 2016

July 14, 2016 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. Detector updates
  2. NIM Papers
  3. fADC125 meeting (Naomi, Cody, Beni)
  4. Other

Minutes

Participants: Sean (NU), Mike (CMU) Eugene, Cody, Luke, Beni, Alexander A., Simon, and Lubomir (JLab).

CDC

- In the analyses meeting Mike reported already his studies on the CDC efficiency.

- Beni: Nick and Chris are cleaning/replacing the CDC HVB that had some issues during the last run due to some dust on them. We discussed possible origins of this dust: coming from the cooling tubes, air, or sucked by the magnetic field.

FDC

- Simon showed first plots about implementing the drift time in the FDC tracking.

- Lubomir studied the magnetic field effects with Garfield and showed that the effect of the avalanche deflection along the wire is equivalent to a wire rotation (of about 10deg for our field) w.r.t. avalanche position. The effect on the time-to-distance relation is equivalent to about 10% increase in the time scale.

- Lubomir showed GENFIT results about the FDC resolution in magnetic field (all results so far presented were without magnetic field): there's strong dependence on momentum and is better than 200 microns at high momenta. There's more work needed on the alignment as seen from some systematics in the residuals shown above.

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