Minutes for HF PWG meeting on 2015/06/25

Rongrong: J/psi vs event activity

- long disucssion on if vertex with rank < 0 cut is necessary or not
- make plot with |vpdvz - vpdtpc|< 3cm
- check number of global tracks matched to ToF to see if there is significant difference for events with rank>0  and without this requirements
- change binning to have more bins at low pT

- preliminary results -
- slide 16 -limit plot range to the fit range (2.5-3.5)
- slide 19: the conclusion could be: relative J/psi production increases faster then the TofMult
- add results from ALICE (slide 14) to backup and compare to STAR results

Barbara: J/psi polarization in p+p 500 GeV
- preliminary estimates of syst. errors
- selected results with reflected bins vs full fit range shown-> all other plots will be posted later
- consistent results compared to previous results
- comparisons with model - NRQCD does not have a prediction power, data constrain the model (the matrix elements)
- lambda invariant - consistent results, no clear sign of problems/discrepancy
- overall results are look solid - no objection to show them at the SQM 2015

Liang: D0 v2{2}
- does like-sign Bg describes combinatorial Bg in the unlike-sign spectrum? - not completely
- v2 vs mass changes from bin to bin - source of systematic error
- slide 6 - like-sing and unlike-sing show different behavior, strange bin-by-bin variation in the v2 of the unlike-sign pairs -> need to check the distributions like thise on slide 3 and 4 for unlike-sign pairs. Need some thoughts how to handle that discrepancy.

- bump in mass spectrum around~ 1.5 GeV: one possible explanation are is D0, d+/- decays other that D0->Kpi, need to check it the bump survive the topology cuts used in the data analysis
- need to include kinematic cuts
- we should check if we have all parents of charmed mesons in the simulations
- open question: what is the effect of correlated background (from jets) on the results?