The following Event Cuts have been incorporated into the analysis:
- |Vz| < 30cm
- Vx2 + Vy2 < 1cm from RMS values
- dNch/dη Cuts for Centrality
- Trigger ID: 86011 Min-Bias Trigger
Event Vertex Distribution in Z with a cut of ±30cm along the Beamline
Event Vertex Distribution transverse to the beam axis with a circle
cut of 1cm around the mean values of the distribution.
Track Selection has been made as follows:
- Using Primary Tracks
- Global DCA < 3.0cm
- Pt correction for energy loss made with π mass assumption
- Track refit with Event Vertex
- Number of Fit-Points > 24
- |yparticle|< 0.1 (particle = π±, K±, p, p)
The Centrality was determined utilizing a Glauber Model simulation performed by Dr. Jim Draper which reproduces the Cu+Cu 22 GeV Reference Multiplicity Distribution:
Cu+Cu 22 GeV Reference Multiplicty for TrigID 86011 and Glauber Model Simulation
Note: Online QA files can be found here (Select Run 5 from bottom, Select Run Period CuCu @ 22GeV from above and click on the select button to display runs.
Reference Multiplicity seperated by Trigger ID. As with the Au+Au 19.6 GeV Dataset, the ZDC trigger was of little use for triggering on central events (see below). The BBC-narrow trigger has been selected for this analysis.
The normal distribution is not see here either since the ZDC does not have good rapidity coverage for the low energy Cu+Cu 22 GeV collisions.
CTB adc sum vs. BBC adc sum
The pseudorapidity distribution is shown for top 10%, 10-20%, 20-30%... centralities.
Cu+Cu 22 GeV collisions had low enough luminosity that they shouldn't suffer from pile up events.
[Insert Rate Plot]
Secondary Vertices were not reconstructed however as we don't expect pileup this should not be an issue
Beam Pipe vacumm was good and beam pipe events were less than 1% of the dataset and only in the peripheral collisions. They can be eliminated with a Mean-Eta vs. CTB multiplicty Cut and/or a Mean-Eta vs. Refmult cut.
Momentum Resolution at Magnetic Field of 0.25T (source: TPC NIM Paper)
Momentum Resolution at Magnetic Field of 0.5T (source: Run4 AuAu 200 GeV Embedding P05ic)