ZDC/SMD readiness*

1
ZDC/SMD readiness

• Sebastian White for
• A.Denisov(COO)
• A.Ster(offline and simulation)
• M.Csanad(online, oncal)
• J.Sikland(online apprentice)
• M.Chiu(Professor Emeritus)
• M.Kaneta(also SMD online)
• n.b.We take no responsibility for set of
  non-working counters called LPC(that is Abhays
  mess)

2
Legacy from Run IV
1)Loss of photostatistics(25) seen in ZDCS1,
less in others -traced to shrinkage of HV
insulating tape on PMTs -tape replaced with
delrin rings -no effect on offline
physics/calibration procedure 2) Unlike ZDC, SMD
not self calibrating -Alexei has done several
Cosmic ray re-calibrations in ZDC lab, most
recent this week to resolve inconsistency in
earlier runs -full calibration of SMD channels
now available.
3
Typical cosmic calibration spectra
4
Legacy from Run IV (cont.)

• Installation/servicing more complicated w. new
  shielding config.
• Nevertheless ZDC now in and used for ZDCLL1 tests
  by S. Belikov, etc.
• We request extension cables to lessen impact of
  carriage moves (otherwise untrained people have
  been ripping cables out of BBC rack)
• HV setting to be chosen for Cu run (see below)

5
Whats new in Run V(CuCu)?

• ZDC is the only calibrated luminosity monitor in
  PHENIX (in AuAu and Au-D)
• It is also the STAR minbias trigger (AA and dA)
• PHENIX puts it back in trigger offline to clean
  up mysteries in BBLL1 and make centrality
• Our luminosity calibrating process will be down
  by 3 orders of magnitude vs. Au
• ie MCDZ4sgA2
• Now simulating aspects of ZDC operation with
  CuCu (Also Soltz is trying to do the same).
  Obvious impact on min bias triggering and
  centrality.

6
Simulation goals

• Andras will (in next 2 months)
• Document his HIJINGafterburner comparisons
• Implement fast MC for ZDC/SMD based on Alexeis
  standalone full geant simulation
• Please cooperate and provide feedback.
• Also need cooperation from LLNL to clean up
  inconsistencies in forward geom definition

7
Highlights from Run IV data
Directed flow, v1, is largest at ZDC location
8
Measure reaction plane in SMD, observe elliptic
flow,v2, in central detectors (copy of SMD also
installed in STAR this year)