Static Tpc Distortions study (present status).

Static Tpc Distortions study (present status).

 
1.Tpc Surveys. https://drupal.star.bnl.gov/STAR/blog/fisyak/2014/feb/19/tpc-survey-0

2.Recheck distortion correction. Mustafa, 2004 data with GG distroted potential, http://www.star.bnl.gov/HyperNews-star/protected/get/startpc/1299/1.html

3.Magnetic and Electric fields in TPC.

Grigory Nigmatkulov used electrons with p ~ 10 MeV/c to measure direction of the STAR magnetic field in TPC.

https://drupal.star.bnl.gov/STAR/blog/gnigmat/2013/aug/22/measurement-magnetic-field

https://drupal.star.bnl.gov/STAR/blog/fisyak/2013/dec/27/measurement-star-magnetic-filed-direction.
It has been observed some asymmetry between East and West direction which was associated with influence of the STAR End cap calorimeter.

 

  Wuzheng Meng (CAD) did calculation for STAR magnetic field accounting the influence of the End cap Calorimeter    

https://drupal.star.bnl.gov/STAR/blog/fisyak/2013/dec/20/asymmetry-star-magnetic-field-due-adding-back-west-pole-tip-extra-magnetic-material

 

4.Outer to Inner sector alignment

1.Alignment with laser tracks. 

         2.Alignment with Cosmics. 
Momentum resolution for cosmics muon withbefore and after the alignment 

https://drupal.star.bnl.gov/STAR/blog/fisyak/momentum-resolution-cosmics-after-magnetic-field-dependent-outer-inner-sector-alignment


5.(Super) Sector to TPC alignment.
It is used 2014 AuAu200 Low Luminosity data. The goal is to find position of Tpc super sector in order  to minimize DCA to primary vertex.
There are some problem with West half of TPC.

 



6.Conclusions