Difference between revisions of "July 18, 2012 Tracking CDC/FDC"

From GlueXWiki
Jump to: navigation, search
(→‎Minutes)
(→‎Minutes)
Line 27: Line 27:
 
Participants: Curtis, Naomi, Beni, Simon, Lubomir, Tim, Mark
 
Participants: Curtis, Naomi, Beni, Simon, Lubomir, Tim, Mark
 
# FDC Update   
 
# FDC Update   
−
## Gas mixture choice: [[Media:GasCompilation.pdf]] Lubomir presented this. The CDC team are not planning to use an organic gas initially, our gas gain is limited by the electronics.  It could be much more useful for the FDC, for which ethane and isobutane look promising, offering higher gas gain for the same or lower HV.  Beni has done some research on who used what and said there were no ageing problems with isobutane alone, more with the other materials that the chambers were built with, in particular tygon and PVC should be avoided. The CMS drift chambers used a gas mix of CO2/Ar with 10% ethane and showed ageing on the wires and cathode strips that was visible through a microscope but did not affect chamber performance.
+
## Gas mixture choice: [[Media:GasCompilation.pdf]] Lubomir presented this. An organic gas could be quite useful for the FDC, ethane and isobutane look promising, offering higher gas gain for the same or lower HV and also suppressing afterpulses.  Beni has done some research on who used what and said there were no ageing problems with isobutane alone, more with the other materials that the chambers were built with, in particular tygon and PVC should be avoided. The CMS drift chambers used a gas mix of CO2/Ar with 10% ethane and showed ageing on the wires and cathode strips that was visible through a microscope but did not affect chamber performance. The CDC team are not planning to use an organic gas initially, our gas gain is limited by the electronics.  The current plan is to design the system for 3 gases but initially implement 2 only.  The addition of a flammable gas means that the exhaust gas will have to be vented outside the hall, not into it.  Also there could be problems if the detectors leak.
 
# CDC Update   
 
# CDC Update   
 
## The new nonmagnetic wire arrived but did not match the sample sent earlier, the new wire's dielectric melts when the wires are soldered.  A replacement batch is expected early next week.  Until then the team are continuing to make hookup wires from the original (slightly magnetic) wire.
 
## The new nonmagnetic wire arrived but did not match the sample sent earlier, the new wire's dielectric melts when the wires are soldered.  A replacement batch is expected early next week.  Until then the team are continuing to make hookup wires from the original (slightly magnetic) wire.

Revision as of 16:37, 18 July 2012

Meeting Time and Place

Wednesday July 18, 2012 at 11:00am At Jefferson Lab, the meeting will be held in F326

Connections

To connect from the outside, please use ESNET

  1. ) ESNET: 8542553
  2. )To connect by telephone, dial:
  • You can look up toll-free number at http://www.readytalk.com/intl
  • US and Canada: (866)740-1260 (toll free)
  • International: (303)248-0285 (toll call)
  • enter access code followed by the # sign: 3421244#

Hardware Agenda

  1. Announcements
  2. FDC Update
    1. Gas mixture choice: Media:GasCompilation.pdf
  3. CDC Update
    1. Prototype dE/dx CDC_signal_integration_new
  4. TDR Update
  5. Calibrations
    1. CDC prototype first attempt at virtual wire wiggling CDC_wiggle_wire_positions

Minutes

Participants: Curtis, Naomi, Beni, Simon, Lubomir, Tim, Mark

  1. FDC Update
    1. Gas mixture choice: Media:GasCompilation.pdf Lubomir presented this. An organic gas could be quite useful for the FDC, ethane and isobutane look promising, offering higher gas gain for the same or lower HV and also suppressing afterpulses. Beni has done some research on who used what and said there were no ageing problems with isobutane alone, more with the other materials that the chambers were built with, in particular tygon and PVC should be avoided. The CMS drift chambers used a gas mix of CO2/Ar with 10% ethane and showed ageing on the wires and cathode strips that was visible through a microscope but did not affect chamber performance. The CDC team are not planning to use an organic gas initially, our gas gain is limited by the electronics. The current plan is to design the system for 3 gases but initially implement 2 only. The addition of a flammable gas means that the exhaust gas will have to be vented outside the hall, not into it. Also there could be problems if the detectors leak.
  2. CDC Update
    1. The new nonmagnetic wire arrived but did not match the sample sent earlier, the new wire's dielectric melts when the wires are soldered. A replacement batch is expected early next week. Until then the team are continuing to make hookup wires from the original (slightly magnetic) wire.
    2. Wiring and testing are proceeding smoothly, currently working on row F.
    3. Gary has started designing a transport cart (with pneumatic tires) to support the CDC whilst it is moved from CMU to JLab.
    4. Prototype dE/dx CDC_signal_integration_new was discussed. Lubomir offered to run some Garfield calculations for the FDC to model the first amplitude peak for different particles.
  3. TDR Update
    1. This is rising nearer the top of the to-do list. A little more progress has been made recently.
  4. Calibrations
    1. CDC prototype first attempt at virtual wire wiggling CDC_wiggle_wire_positions was discussed. Mark suggested looking at left/right differences in residuals to distinguish time errors from position errors.
Retrieved from "https://halldweb.jlab.org/wiki/index.php?title=July_18,_2012_Tracking_CDC/FDC&oldid=38796"