sPHENIX is a new detector at RHIC.

["Aidala, Christine" <caidala AT bnl.gov>]

Dear all,

 

Below are minutes from today’s (lengthy!) General Meeting.

 

Christine

 

-- 

Christine A. Aidala
Associate Professor
Department of Physics
University of Michigan
(734) 764-7611

 

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Collaboration News – Dave Morrison

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Recently first sPHENIX workshop in China was in late April.  Also MVTX workfest at MIT last week.

 

May will be a busy and consequential month!  QM and OPA CD-1 review.  Review sessions _must_ have a functional remote connection at all times.

 

Collaboration meeting June 5-6 at BNL—please register: https://indico.bnl.gov/event/4552/overview

 

PAC meeting June 7-8.  One talk on sPHENIX science, one on sPHENIX as baseline for an EIC detector.  RHIC Users’ Meeting June 12-15.  sPHENIX plenary speaker TBD.

 

 

Project News – Ed O’Brien

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HCal steel order now placed.

 

Plenary talk practices for OPA CD-1 review took place May 2.  Talks need to be frozen and posted for the committee next week.  Resource-Loaded Schedule already frozen.

 

OPA CD-1 Review Committee composition/structure has changed slightly.  Single subcommittee responsible for calorimetry and tracking.

 

High priority items for project include demonstrating with simulations that the Key Performance Parameters can meet Mission Need.  Also high priority to get MOAs with other BNL departments in place.

 

Looks promising to restore original calorimeter scope through international contributions.

 

 

Report on the first sPHENIX workshop in China, Apr 22-23 – Huan Huang, Yajun Mao

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CIAE will apply for sPHENIX membership soon.  Means that all high-energy nuclear physics groups in China will participate in sPHENIX.  With all groups interested, should create very strong case for funding!

 

Goals of workshop were to introduce sPHENIX science + detector to Chinese Nuclear Physics community, organize the Chinese sPHENIX Consortium, identify hardware + software projects, and establish close collaborations with other sPHENIX groups.  Very successful workshop with respect to these goals.

 

EMCal Project – Chinese groups work towards 20% EMCal contribution.  Have identified production sites in Shanghai and Beijing.

 

MVTX Project – Strong interest from several groups.  Can contribute to software and simulation in near term, possibly assembly in longer-term.  Details to be worked out.

 

 

Report from MVTX workfest at MIT – Ming Liu

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Goals of workfest – Discuss and refine a roadmap for MVTX realization.  ~20 attendees.

 

ALD requested “mini-review” of sPHENIX tracking integration late June or early July.  Nils Feege should be involved in integration discussions to give input on compatibility with an EIC detector.

 

MVTX test beam at Fermilab was successfully performed Feb-March with 4-sensor telescope and full readout.  Hit spatial resolution < 5 microns.  Joint MVTX+INTT test beam at Fermilab planned for Jan-Feb 2019.

 

Broader MVTX physics program being considered, including charmed baryon measurements, directed flow of D and Dbar, and guon distributions in nucleons/nuclei at EIC.

 

ALD in discussions with DOE.  Current prospective funding profile would mean installation in June 2022.  There appears to be significant support for MVTX from BNL management at this point.

 

 

Introduction to discussion of Ultimate Performance Paramaters (UPPs) at CD-1 review – Gunther Roland

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Emphasized need to relate UPPs to physics goals.  Need to be careful not to overpromise, but also not to undersell expected capabilities.

 

 

Status of Au+Au jet performance plots for CD-1 review – Dennis Perepelitsa

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Updated set of mean pT response and pT resolution plots.  UPP for jets: sigma/mean = 15%/sqrt(pT) [GeV] for R=0.2 jets in central Au+Au.  For each R, can find a minimum jet pT above which resolution is at least this good—pT > 20 GeV for R=0.2.

 

Comparison to results at Dec 2017 Collaboration Mtg. shown – significant contribution to difference from instrumented steel vs. uninstrumented aluminum IHCal and change in eta coverage.

 

Decomposition of jet energy resolution shown.

 

 

Tracking performance parameters – Tony Frawley

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Only recently have fast enough code to make good estimates of upsilon resolution embedded in central HIJING.    Results show that we are not presently capable of meeting the 100 MeV goal for upsilon mass resolution.  This is the performance parameter that will be most difficult to meet in realistic running conditions.  Keep in mind that these studies assume no MVTX, as appropriate for the CD-1 review. 

 

SAMPA chip shaping time assumed makes a difference in mass resolution.

 

Dependence of mass resolution on occupancy needs to be understood better.

 

Worst case with configurations studied is 119 MeV upsilon mass resolution for central Au+Au and 200 kHz pileup rate.

 

 

Ultimate Performance Parameters for the EMCal – Craig Woody

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Original sPHENIX MIE in 2012 cited a required EMCal resolution of 15%/sqrt(E), based on what we thought we needed to measure jets and upsilons.  In general, doesn’t make any sense to quote an energy resolution goal without a constant term.  Moreover, the updated energy resolution UPP should take into consideration the vast amount we have learned from the four beam tests we have had since then.

 

We need to decide how to report UPPs for the review.  Should be simple.  Proposed UPPs on p. 15 tentatively seem reasonable:

 

Photons – Minimum energy resolution (say < 10%) for minimum energy we plan to measure (say 15 GeV).  These example  values would be achievable.

 

Upsilons – Cite an e/h rejection of > 100:1 at 4 GeV

 

For CDR, propose to specify energy resolution as sigma/E = 16%/sqrt(E ) [GeV] + 5% for single particles and include a noise term of 20%/E [GeV] for central HI events.

 

 

 

 

From: sPHENIX-l <sphenix-l-bounces AT lists.bnl.gov> On Behalf Of Gunther M Roland
Sent: Thursday, May 3, 2018 1:06 PM
To: sphenix-l AT lists.bnl.gov
Subject: [Sphenix-l] Draft agenda for 49th sPHENIX General Meeting tomorrow

 

 

Friends,

 

The draft agenda for tomorrow's meeting can be found at:

https://indico.bnl.gov/event/4606/

 

In addition to collaboration and project news, we are expecting reports from the China workshop and MVTX workfest, as well as a discussion of the jet, tracking and photon performance and related "Ultimate Performance Parameters".

 

Best,

 

Gunther and Dave