HF PWG Meeting Minutes by Zhenyu - 2015/02/12

1) Primary Vertex Refitting for D Meson Simulation Studies - Mikhail
Mikhail studied KFVertexFinder to reconstruct primary vertices in simulation. He found that by removing daughter particles from potential D0 candidates, the primary vertex position resolution can be improved significantly. One thing not fully understood is the vertex reco efficiency is higher in MB than D0 events, which is different from naive expectation. Zhenyu pointed out that this could be due to bias from D0 daughters if they are not removed, or due to less number of tracks using in vertex reconstruction than MB.

Action items:
1. require IST hit in the future, instead of PXL only
2. check the extra time it takes to run KFVertex Finder to see if this should be done at picoDST produciton, or analysis code level
3. ask Yuri whether he could make KFVertexFinder more user friendly so that one could directly call it in such studies
4. plot vertex efficiency vs number of actual tracks used in vertex finding to understand the 

2) D0 Reconstruction Efficiency in Simulations with HFT in 200GeV p+p Collisions - Liang
Liang presented D0 reco efficiencies in simulations with/w.o. removing D0 daugthers in primary vertex reconstruction. It is found that the D0 signal significance is increased by removing D0 daughers, consistent with Mikhail's observation.

Action items:
1. make sure the results/numbers presented in the slides are consistent

3) 
Upsilon in U+U 193 GeV Run12 - Robert
Robert presented Upsilon yields from simultaneous signal and background fit, and latest systematic uncertainties. He would like to move towards publication with Upsilon results alone, while keep the option open to include Jpsi results if they can be ready in time. 

Action items:
1. send a paper proposal to the HF list - done.

4) D* in pp 500 GeV Run11 - David
David reported after applying additional pT smearing (~0.5%*pT) extracted from Barbara's J/psi analysis, the D* invariant mass mean and width are consistent between data and toy models. David also did full error propagation for trigger efficiency uncertainty calculation. Previous theoretical calculations were scaling D0 to D8. Calculations from Ramona and Matteo on D* are available and there is a difference. David updated the plots with these new calculations. David said that he is working on the analysis note and paper draft and will be sent to the PWG
 soon.

Action items:
1. Zhenyu asked whether the need for such additional smearing, giving its relative large size, has been reported by other analyses. The answer is yes, according to Xin/Yifei's dilepton analyses
2. AN and paper draft.