HF PWG Meeting Minutes by Zhenyu - 2014/10/23

1) MTD data production strategy for Run 14 - Group discussion
The HF PWG group supports the general idea of the MTD group's proposal about Run14 dimuon-triggered event data production strategy, i.e., identify and reconstruct only those events in which there are at least two tracks matched with MTD hits that fired the MTD trigger. The detailed procedure and cuts should be presented and discussed with the HF PWG before the production starts. 

2) Run14 PicoDst Structure Update - Rongrong
Rongrong presented the latest PicoDst structure and estimate of disk space. By separating the TOF and EMC PID info from the general StTrack branch into new branches, and by switching off TofHit branch, the disk space is reduced by a factor of two (One student will double-check it together with Xin). Hao raised a concern that v3 and J/psi-h correlation measurements won't be possible if we don't keep all the tracks and save only electron and muon candidates. It was agreed that since the size of reconstructed di-muon triggered events will be reduced by at least a factor of 10, we store all the tracks to not losing interesting physics. It was also requested to include HT and central triggered samples to estimate the total disk space. Rongrong agreed to add those. A document about the PicoDst structure is also distributed by Rongrong.

3) J/psi in Au+Au 200 GeV Run10 vs Run11 - Wangmei
Wangmei reported results to investigate the discrepancy in J/psi yields between Run10 and Run11. He found a bug which only affected 200 GeV data, where the nSigma_dEdx cut efficiency was extracted based on a different nSigma_dEdx cut than what was applied to data. The discrepancy between Run10 and Run11 is greatly reduced. However, some of the plots are not consistent with each other. Wangmei should check his plots to make sure the plots in the slides are correct. It was also requested that J/psi invariant mass spectra both before and after background subtraction, and before and after bug fix should be made included in the slides.

4) Upslion in p+p 500 GeV - Leszek
Leszek reported new nSigma_dEdx cut efficiency estimated based on photonic electron sample. Questions were raised on the jump in the fitted nSigma_dEdx Gaussian sigma at 6 GeV/c and the negligible like-sign yields in photonic electron sample extraction. Leszek will look into these. Leszek only presented EMC cut efficiencies estimated from embedding, and from data with Upsilon (single electron?) candidates. It was suggested that he should adopt the same method to extract these efficiencies using the photonic electron sample, while taking into account the correlation between different cuts. It was also suggested that he should think about doing the same for L0 trigger efficiency. And finally, it was suggested that he should use "data" instead of "MC+data" efficiency for final result extraction. 

5) NPE in p+p 200 GeV Run12 - Xiaozhi
Xiaozhi presented low Pt NPE
 TOF cut and TOF matching efficiencies extracted from photonic electron samples. The TOF matching efficiency was found to be too good to be true and Xiaozhi was asked to check his code. Xiaozhi presented his embedding requests. While there was no question on the request, it was suggested that Xiaozhi could extract the NPE yield using the existing high-pT embedding sample, so that he could compare with his high-pT and Olga's Run09 results. It was agreed that the request can be submitted to embedding list in a couple of days while Xiaozhi doing the other study.