1 Jim Thomas – The Berkeley Lab Three Abstracts for QM 2011 Instrumentation Session The Heavy Flavor Tracker (HFT) The Muon Telescope Detector (MTD) A High Level (Online Tracking) Trigger for STAR (HLT) Flemming Videbaek, EPD, plus JT, et al. LiJuan Ruan, et al. Aihong Tang, et al.

2 Jim Thomas – The Berkeley Lab The STAR Detector hello MRPC ToF barrel 100% ready for run 10 (now!) BBC PMD FPD FMSFMS EMC barrel EMC End Cap DAQ1000 FGT Completed Ongoing MTD R&D HFT TPC FHC HLT

3 Jim Thomas – The Berkeley Lab The HFT – The Question Spyros Margetis

4 Jim Thomas – The Berkeley Lab The HFT – The Challenge The STAR HFT has the capability to reconstruct the displaced vertex of D 0  K   (B.R 3.8%, c  = 123  m) Λ c   Kp (B. R. 5.0%, c  = 59.9  m) and more … Primary Challenges –Neutral particle decay –Proper lifetime, c , 123  m –Find a common vertex away from the primary vertex –Identify daughters, measure p T, and reconstruct the invariant mass

5 Jim Thomas – The Berkeley Lab The HFT – The configuration Beampipe SSD IST Pixel Detector 0 The HFT puts 4 layers of Silicon around the vertex Provides ~20  m space point resolution on tracks Works at high rate (~ 800 Hz – 1K) Does topological reconstruction of open charm Will be ready for the 2014 run

6 Jim Thomas – The Berkeley Lab The HFT – Technology

7 Jim Thomas – The Berkeley Lab The MTD - Design Concept A detector with long-MRPCs covers the whole iron bars and leave the gaps in- between uncovered. Acceptance: 45% at |  |< modules, 1404 readout strips, 2808 readout channels Long-MRPC detector technology, HPTDC electronics (same as STAR-TOF)

8 Jim Thomas – The Berkeley Lab A large area of muon telescope detector (MTD) at mid-rapidity, allows for the detection of di-muon pairs from QGP thermal radiation, quarkonia, light vector mesons, possible correlations of quarks and gluons as resonances in QGP, and Drell-Yan production single muons from the semi- leptonic decays of heavy flavor hadrons advantages over electrons: no  conversion, much less Dalitz decay contribution, less affected by radiative losses in the detector materials, trigger capability in Au+Au trigger capability for low to high p T J/  in central Au+Au collsions - excellent mass resolution, - separate different upsilon states - e-  correlation to distinguish heavy flavor production from initial lepton pair production The MTD - Physics Motivation

9 Jim Thomas – The Berkeley Lab The MTD - Single Muon and J/  Efficiency J/  efficiency 1.muon efficiency at |η| 2 GeV/c 2.muon-to-pion enhancement factor: muon-to-hadron enhancement factor: including track matching, TOF and dE/dx 4.dimuon trigger enhancement factor from online trigger: in Au-Au (central collisions) G. Lin, Yale Univ.

10 Jim Thomas – The Berkeley Lab The MTD - High Mass Di-muon Capabilities 1.J/  : S/B=6 in d+Au and S/B=2 in central Au+Au 2.With HFT, study B  J/  X; J/    using displaced vertices 3.Excellent mass resolution: separate different upsilon states Heavy flavor collectivity and color screening, quarkonia production mechanisms: J/  R AA and v 2 ; upsilon R AA … Quarkonium dissociation temperatures – Digal, Karsch, Satz Z. Xu, BNL LDRD ; L. Ruan et al., Journal of Physics G: Nucl. Part. Phys. 36 (2009)

11 Jim Thomas – The Berkeley Lab Distinguish Heavy Flavor from Initial Lepton Pair Production: e-  Correlations e-  correlation simulation with Muon Telescope Detector at STAR from ccbar: S/B=2 (M eu >3 GeV/c2 and p T (e  )<2 GeV/c) S/B=8 with electron pairing and tof association MTD: construction starts in FY2011; project completion in FY2014 Z. Xu, BNL LDRD ; L. Ruan et al., Journal of Physics G: Nucl. Part. Phys. 36 (2009) NA60, PRL100,022302(2008) R. Rapp, hep-ph/

12 Jim Thomas – The Berkeley Lab The MTD - Summary Charm contribution to di-lepton spectrum measurement is essential to obtain the thermal radiation from QGP and understand in-medium modifications of vector mesons at RHIC. MTD will advance our knowledge of Quark Gluon Plasma: - trigger capability for low to high p T J/  in central Au+Au collsions - excellent mass resolution, separate different upsilon states - e-muon correlation to distinguish heavy flavor production from initial lepton pair production - rare decay and exotics … - different background contribution provides complementary measurements for dileptons The prototype of MTD works at STAR from Run 7 to Run 10. L. Ruan et al., Journal of Physics G: Nucl. Part. Phys. 36 (2009) ; ; Y. Sun et al., NIMA 593 (2008) 430. The larger Run 11 modules with slightly wider readout strips show a comparable performance as the modules in Runs 7-10, based on cosmic ray tests at USTC and Tsinghua.

13 Jim Thomas – The Berkeley Lab The HLT SL3 GL3 BEMC TOF  GL3  HFT MTD Total 24 SL3 machines Sector tracking (SL3) in DAQ machines (24 in total, one per TPC sector) Information from subsystems (SL3 and others) are sent to Global L3 machines (GL3) where an event is assembled and a trigger decision is made.

14 Jim Thomas – The Berkeley Lab Over the next five years RHIC is expected to increase its delivered luminosity to 8x10 27 cm -1 s -1 for AuAu collisions at 200 GeV and 6x10 31 cm -1 s -1 (1.5x10 32 cm -2 s -1 ) for pp collisions at 200 (500) GeV. To cope with the high collision rate, STAR has upgraded the DAQ system. The improved data taking capability, imposes a challenge for STAR –computing resource in terms of CPU time and tape storage –Data analysis: struggle with large data volume and suffer long analysis cycles By implementing an HLT it will be possible to reduce the amount of data written to tape by selecting desirable events while still maintaining a high sampling rate. The HLT will fully utilize the delivered luminosity for a wide range of triggers. With the HLT, all the upgraded components will be able to perform at their full potential and will be performing beyond STAR’s current trigger capabilities. The HLT - Motivation

15 Jim Thomas – The Berkeley Lab The HLT – Physics agenda Heavy flavor measurement, EM probes J/ψ production and flow for exploring the unexpectedly fast thermalization at RHIC. Access in-medium modification of vector mesons via di-lepton invariant mass spectra. Search for exotics strangelets, antimatter, hypernuclei etc. High pt probe energy loss, jets Interesting physics with the HLT, fast output with the HLT

16 Jim Thomas – The Berkeley Lab The HLT – Tracking performance

17 Jim Thomas – The Berkeley Lab The HLT – Recent physics results Anti-α discovered ! Paper submitted to Nature. Without HLT, STAR would have eventually seen anti-α but LHC is trying to scoop us. It is a race to the publisher.

18 Jim Thomas – The Berkeley Lab The HLT – Recent progress on R & D Potential for new discoveries. Computing intensive, must use GPU acceleration. R & D is ongoing. Topology triggers

19 Jim Thomas – The Berkeley Lab The HLT – Recent progress on R&D – online  ’s V0 finding runs 60 times faster than the standard CPU v0 finder, after optimizing the algorithm with GPU acceleration. An online farm of 20 – 60 PCs with GPU is needed. Experience gained can benefit other computing intensive tasks.

20 Jim Thomas – The Berkeley Lab The HLT – Recent progress on R & D Precision comparable to offline when combined with HFT hits. Vertex finding

21 Jim Thomas – The Berkeley Lab The HLT – Summary With HLT we can do compelling physics fast (this is proven !) Good physics potential with GPU upgrades. R & D is progressing well.

22 Jim Thomas – The Berkeley Lab FY09FY10FY11FY12FY13FY14FY15 HFT Construction HFT Operation MTD Construction MTD Operation HLT Development HLT Operation Finish HFT in time for the 2014 run Finish MTD project by Mar, 2014 and make 80% of the full system ready for year 2014 run HLT funded and under development through FY15, but continuously available Three projects – Three Compatible Schedules $2.5 M $1.7 M $14-16M