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[videbaek <videbaek AT bnl.gov>]

TPC meeting 2/22 2024
Present : Jim,Yuri,Tommy, Gene and Flemming

Hardware
  Last repairs of RDO (2) should be done in next two weeks; closeout 
approaching
  Alexei reported during week
“I finished measurements of target displacement on TPC wheel versus 
actual position. For all holes target dropped vertically down due to 
target gravity.
 I did only inner holes on wheel. There are too  difficult to measure 
others.”
And provided numbers to Yuri. Resoultion in survey should be around 150 
microns.

Software
a)  work on space charge calibration of pp 200 for 2022 has continued . 
Studied 5 fills with high statistics.
The runs are long and some jobs were killed due to 3 day limit.
Comparisons of fill vs ZDC rate shows
1) nice linearity with ZDC rate which is good
2) significant difference between fills corresponding to 4-5 mm DCA.
So seems necessary to have space charge done per fill.

b) Continued looking at matching between TPC and BEMC towers. Confirmed 
that indeed the phi-definitions are same between subsystems as should 
be. So issue of reduced matching is in area behind sector 18. Other 
plots (e.g. h+/h- issues) does not show any issues with sector 18 vs. 
time.
Gene suggested looking if it could be a BEMC issue electronics. Matching 
looked slightly off.

c) discussion on track matching to eTOF, that was also the subject to an 
earlier meeting today. New information appear during meeting, and issue 
may very well be a space charge issues. Have suggested eTOF group to 
review matching in FF and RFF setting for OO system to confirm this is a 
space charge driven.




--
Flemming Videbaek
senior scientist, emeritus
videbaek @ bnl.gov
Brookhaven National Lab
Physics Department
Bldg 510D
Upton, NY 11973

phone: 631-344-4106
cell     :  631-681-1596