The STAR experiment

1) Trigger requirements for Run23

• What detector or combination of detectors, i.e. VPD, ZDC, BBC, EPD, should be used to define the MB trigger?
• Is a vertex z cut needed for the MB trigger? If so, what is the range (30, 70, 100, or something else)?
• What are the desired thresholds for BHT triggers? What is the setup for the dimuon trigger? Do they need a vertex z cut? If so, what values? 

Minutes:
- Conveners will bring this up for discussion at the PWG meetings next week. All PWGs are expected to present a list of required triggers at the trigger boarding meeting on April 3rd.

2) How to run BSMD in 2023-25

• Essentially no spare parts to fix any failed components
• Do we want to turn it on for low-lumi AuAu, pp, pAu?

Minutes:
- HP PWG will discuss this topic, and inform the trigger board.

3) Centrality calibration for BES-II COL

• 7.7 GeV: Zuowen Liu, Chenliang Jin, Emmy Duckworth
• 9.2 GeV: Emmy Duckworth
• 11.5 GeV: Chenliang Jin (looking for a second person to join Chenliang)

Minutes:
- We asked the volunteers to make this work their high priority in the next weeks to hopefully finish it before QM abstract submission.
- Need one more volunteer for 11.5 GeV centrality calibration

4) Data on distribution disk

• Run15 pp, pAu data sets, P16id MuDst: still needed

Minutes:
- ColdQCD PWG will follow up on this

1) Run23 trigger discussion

• FCV (SLIDES)
  
  • ZDC MB trigger with rates close to 10K, with moderate swing (every 10K change leads to 2% systematics).
    • No VPD/BBC/EPD coincidence.
    • No online Vz requirement using VPD.
    • Crossing angle of 0.2-1 mrad to restrict Vz (too large crossing angle will affect ZDC triggering efficiency).
  • Need 20B MB events with |Vz|<30 for CME search.
    • ZDCSMD should be present in such events for CME search.
  • A special trigger to detect γ+Au events utilizing East-West asymmetric activity (details proposed).
    • FTS must be present in the triggered γ+Au events.
• LFSUPC
  • ZDCMB
    • Need |vz| < 30 cm for dielectron analysis. No need to cut online if TPC vz distribution is similar to 2019 (83% of events within |vz| < 30 cm over all MB events)
  • UPC triggers (SLIDES)
• HP (SLIDES)
  • dimuon+zdc_coin+vpd100
  • BHT1+zdc_coin+vpd10
  • BHT2+zdc_coin+vpd100 
  • BHT3+L2gamma
  • monitor triggers: vpd-zdc-novtx, vpd-zdc-10

Minutes
- Nihar and Prithwish will present on Monday at trigger board meeting
- If one imposes a TofMult > 1 requirement on ZDCMB trigger, it might reject phi mesons in UPC. Need further discussion
- Need to follow up on whether ZDCMB has any inefficiency for ultra-central collisions. One can probably run a monitor trigger to check it with data. 

2) BSMD running strategy

• HP
  • Highest priority: run it during high-lumi Au+Au
  • Can opt to turn off BSMD during low-lumi Au+Au
  • Assess BSMD condition in Run23 to decide whether to turn it on in Run24 for pp

1) QM 2023 abstracts (LIST)

• 87 oral abstracts proposed. Need at least a factor of 2 reduction
  • QM 2022: 37 submitted, 21 accepted
• Decision on an abstract: please take into account the feasibility and maturity of the proposed analyses when making a decision
  • Submit as it is as an oral presentation
  • Merge with other abstracts, and submit as an oral presentation
  • Submit as it is as a poster presentation
• In case of merging
  • PAs can prepare a few other merged abstracts to be submitted as poster presentations 

Minutes:
- Each PWG will discuss abstract merging in the next week or so. We aim to submit about 40 oral abstracts to the conference. 
- Will contact the forward upgrade group for a possible QM abstract

2) Embedding needs for QM23 (list)

• Please check if anything is missing
• Embedding team will produce at least a test sample for each requested embedding before Apr. 30th

Minutes: everyone is encouraged to check the list of embedding requests needed for QM23. If anything is missing, please notify the PWG. 

3) Run23 trigger: feedback from trigger board meeting

Minutes: homework given by the trigger board
- Define the vertex criteria for desired good events
- Design trigger for photon-nucleus process
- Suggested to use VPD100 instead of VPD10 for BHT1 trigger
- Determine the HT trigger threshold for J/psi analysis

4) PWG QA helpers

• CF:  Yevheniia Khyzhniak (Ohio), Muhammad Ibrahim Abdulhamid Elsayed (Egypt)
• FCV: Niseem Magdy (SBU), Han-Sheng Li (Purdue)
• HP: Andrew Tamis (Yale)

Minutes:
- Still need to find QA helpers from LFSUPC and ColdQCD
- It is suggested to reach out to institutions that could not fulfill their shift duties due to travel restrictions. 
- The main responsibilities of the helpers are: i) produce weekly QA report to QA board based on fast offline data; ii) perform timely QA on official data production


5) Run21 O+O data QA: /star/data14/GRID/NFS_FileList/production_OO_200GeV_2021_physics_P23ib.picodst.txt

• bTOF/VPD calibration was not included

Minutes: will likely reproduce the RFF dataset once the bTOF/VPD calibration is ready

Target journal: Science

NOTES

2) Organizational news

• Cold QCD convener rotation: Maria Zurek -> Jae D. Nam

3) QM 2023 abstracts (LIST)

• Abstract length limit: 350 words

4) Data production

• Run21 OO 200 GeV: reproduction with correct BTOF/VPD calibration done with SL23c

Minutes: no changes in TPC tracking

5) PWG QA helpers for Run23

• CF:  Yevheniia Khyzhniak (Ohio), Muhammad Ibrahim Abdulhamid Elsayed (Egypt)
• FCV: Niseem Magdy (SBU), Han-Sheng Li (Purdue)
• HP: Andrew Tamis (Yale)

Minutes: looking for additional helpers from LFSUPC and ColdQCD PWGs

6) A recent study by Bassam (TAMU) to separate pi/k/p up to high pt with 2D fitting based on Run15 pAu data (SLIDES)

• TPC nSigma: a skewed Gaussian distribution
• TOF nSigma: a correlated double-Gaussian function
• Need to perform the fit in small eta bins

2) February collaboration meeting (Meeting page)

• Speakers for PWG reports
• Tuesday: joint parallel session on BES-II analyses (LFSUPC/CF/FCV)
• Wednesday: special plenary session between 4:30-5:45 pm LBNL time
• Fill in the parallel session agenda on Drupal
• Management-convener meeting: Wednesday 6-8 am LBNL time
  • Inputs for discussions?

Conclusions: all BES-II analyses are expected to be presented during the joint session on Tuesday. LFSUPC/CF/FCV conveners will collect the contributions and work on the agenda. 

3) data production

• DAQ -> PicoDst: 9.2 GeV done; 11.5 GeV to be started soon

4) How to estimate the tracking efficiency uncertainties?

• Dedicated task force is finalizing their work, but it could still take some time. 
• Before that, we should try to be consistent across the collaboration. We suggest to include both sources in the results:
  
  • Uncertainty on the absolute efficiency: 5% (relative) without any pT dependence (not relevant for relative yield measurements, such as flow)
  • Uncertainty on the embedding performance: vary the cuts (DCA, NHitsFit, ...) simultaneously in data and embedding and check the impact on the results. Then one takes RMS of the variation as the uncertainty, which could be pT dependent.

Conclusions:
- There might be some overlap in the two sources resulting in some overestimation, but this is probably the best we can do now unless/until new information becomes available
- For particles reconstructed from N daughters, we think the uncertainty should be N*5%, not sqrt{N}*5%
- To get the RMS as the uncertainty, it might be better to try different variations on the track quality cuts
- Conveners will discuss this within PWGs and collect feedback

3) February collaboration meeting (Meeting page)

• Speakers for PWG reports
• Tuesday: joint parallel session on BES-II analyses (List of contributions)
• Management-convener meeting: Wednesday 6-8 am LBNL time
  • Inputs for discussions?

Minutes:
- Since there are more contributions than we can accommodate for the joint parallel session on Tuesday, conveners will select the ones that will benefit the most from cross-PWG discussions and schedule them on Tuesday. The rest of BES-II talks will be scheduled on Wednesday, when each PWG will have parallel sessions on their own

AOB
- STAR forward meeting on Tuesday (Feb. 21st) at 8:30 am: discussion on what different physics analyses need from forward tracking, calorimetry and so on, to be successful. Anyone wants to present the needs for his/her analysis should request a slot by contacting Elke. (https://drupal.star.bnl.gov/STAR/event/2023/02/21/STAR-Forward-Upgrade-Meeting)
- Collect embedding needs for QM abstract submission. VERY IMPORTANT

• FCV: LIST
• CF: LIST
• LFSUPC: LIST
• HP

1) Organizational news

• ColdQCD: Ting Lin (incoming), Qinghua Xu (outgoing)

2) February collaboration meeting (Meeting page)

• Tuesday: joint parallel session on BES-II analyses (List of contributions)
  • Zoom link: https://lbnl.zoom.us/j/95581269963?pwd=d3JOZndhSnRGaDg1YndNSnJkZGJLUT09
• Management-convener meeting: Wednesday 6-8 am LBNL time
  • Inputs for discussions?

Minutes: FCV/LFSUPC/CF conveners will work out the agenda for Tuesday's joint session together, and then upload to the Drupal page. 

3) Collect embedding needs for QM abstract submission

• FCV: LIST
• CF: LIST
• LFSUPC: LIST
• HP

Minutes:
- Analyzers, who plan to submit QM abstracts on analyses needing embedding that are not produced yet, should inform PWG their needs as soon as possible
- Current list of embedding needs for QM can be found here (LIST), which will be continuously updated.