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PHENIX Run-6 BUP. Abhay Deshpande For PHENIX Collaboration RHIC Spin Collaboration Meeting October 5 th , 2005. Status of PHENIX BUP-Run-6. It is NOT done yet! It is being prepared, discussed and debated within PHENIX as we speak
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PHENIX Run-6 BUP Abhay Deshpande For PHENIX Collaboration RHIC Spin Collaboration Meeting October 5th, 2005
Status of PHENIX BUP-Run-6 It is NOT done yet! It is being prepared, discussed and debated within PHENIX as we speak My understanding is that it will be submitted to Sam Aronson on October 7th or about then, along with STAR’s
Outline • Run-5 production status • Run-5 data expectation for physics • Luminosity & polarization expectations from Run-6 from Fischer/Roser document (July 2005) • What is certain and what is not…. • PHENIX Spin Beam Use Request • PHENIX plans for later years and HI requests
Run-5 Data Status • PHENIX Run-5 pp data • Moved to CCJ/RIKEN in almost real time during the run • Production software setup • a year in advance: Run-4 run a practice run • Production started within a week of Run-5 pp end • Production ends in September’05 • Focus on Central Arm Data Only • Higher level triggers in data tagging mode, mostly with high minimum pT cut • Set priority highest for p0 analysis: • Data analysis for relative luminosity uncertainty, EMCal Calibration, EMCal TOF calibration, Local Polarimeter etc. started immediately. • Approx. 30-40 times better P4L than (Run-3/4 combined) • Spin Fest ‘05 in Wako Japan, started the analysis in earnest • Results to be released in PANIC’05 end of October • Full data production including muon arms about to begin at CCJ
Run 5 Data Expectations • Physics Results: • Cross section & single & double spin asymmetry in p0 production • Double spin asymmetry in h production • Spin correlations with kT in double longitudinal asymmetries • Direct photon cross section study • Jet production double spin asymmetry • Charged hadron asymmetry cross section and single/double spin asymmetries • Single and di-muon production cross sections and asymmetries • J/Psi production asymmetries & cross section
Luminosity & Polarization Guidance • July 2005, “Fischer-Roser” document with other authors • PHENIX takes 70% of the maximum delivered luminosity as a guide and takes the polarization estimate directly as suggested by this document • Further we take 30% of the delivered luminosity as that written to tape: • 9 pb-1 /wk => 0.21 x 9 pb-1 = 1.9 pb-1 to tape at 60% pol. per week • Typically 60-80% of this passes the data QA tests
Guiding Philosophy for Run-6 Planning • As indicated to DOE in February, we would want 275 pb-1 integrated delivered luminosity by mid 2009 • 10 weeks per year from now until 2008 and 5 wks in 2009 • This finishes the 200 GeV CM physics program with all its goals • Internal shuffling of physics weeks amongst the runs as long as it is advantageous to the spin run should be entertained • Whatever running CAD says it will require to achieve the above delivery goal is non-negotiable • Note that only 50% polarization was achieved, and that too at less than optimal luminosity using the cold snake, at the end of Run-5. Understanding this is of paramount importance! • Whatever running the beam polarimetry group says it will need to get to the 5-7% beam polarization accuracy from Run-6 onwards should also be non-negotiable
Taken from Research Plan for Spin Physics at RHIC, February 11, 2005
What could we get in Run-6? • In 10 wks about 15 pb-1 (3.5 times better than Run5) or in 15 weeks (23 pb-1), ~5 times better than Run-5 • If no HI request then 23 pb-1 looks interesting BUT • PHENIX HI, strongly interested in Running Au-Au • Believe they can take 4-5 times the Run-4 Au-Au luminosity • Improvement mainly comes from: • 1.5 times luminosity improvement compared to Run-4 • 2.5 times comes from DAQ bandwidth improvements and possibilities of using Level 2 triggers, overall PHENIX operations improvement • Heavy Flavor Physics the main motivator and have decided they need in all 10 times Run-4 statistics. 4 times this year and another large set in Run-8 • COMPELLING Case for the QGP investigations! This program is also in the discovery phase!
PHENIX Spin View & Request • In our view with 10-15 weeks, no fundamentally new physics goals can be reached with longitudinal beam polarization. • Any longitudinal running will contribute towards the integrated luminosity goal of 275 pb-1 (fundamentally NEW goal e.g. ALL direct photons) • Do not demand a long longitudinal run in Run-6 • willing to give up the longitudinal part of the run in favor of additional weeks in Run-7 (higher polarization higher probability) • In Run-6 CAD should get sufficient time and opportunity for: • Polarization and luminosity development using cold snake • 500 GeV CM energy development • Beam polarimetry development and calibrations • A short run to demonstrate the success of machine development could be extremely fruitful if run TRANSVERSELY in PHENIX with RADIAL beam polarization to explore the Sivers function. The length of this run could be between 3-5 wks. • Even if this turns out to be zero, the AN measurements with these will be significantly better than a recently published data set by PHENIX OPTIONAL 10 wks pp = 3-4 wk (Trans) + 2-1 wk 500 GeV (Trans) + 5 wk 200 GeV (Long)
Sivers Function Measurement • Boer and Vogelsang, Phy. Rev. D69, 094025, 2004; hep-ph/0312320 • A non zero Sivers function means that there will be a left/right asymmetry in the kT of the partons in the nucleon • This asymmetry will lead to an asymmetry in df distribution of back to back jets (more jets on the left vs. right for positive Sivers function) • Should also be able to see this with fragments of jets (hadrons) • We studied this assuming radial polarization (for PHENIX’s east-west acceptance/geometry) • A vertical polarization -- reduces the significance of the result by factor ~3 (M. Chiu & W. Vogelsang)
Run-6 Radial Polarization at PHENIX • Sivers distribution is a transverse parton momentum distribution correlated with nucleon’s spin axis, which could arise from orbital angular momentum • Sivers function measurement in PHENIX from Run-6 will be one of the early measurements of non-zero transverse spin effects which would prove existence of orbital angular momentum and possible cause of low DG (if present results pass the test of time) • Blue Curve: Fig.3 from hep-ph/0312320 • Red Curve: Blue curve after accounting for di-hadron smearing and realistic polarization • Error bars: Expected sensitivity with 60% beam polarization and ~7 pb-1
Why transverse physics now? While the main goal of PHENIX Spin are • polarized gluon distribution • flavor separation of polarized parton distribution using W production and weak decays the field of transverse spin effects has grown in the recent times with the observation of unusual and unexpected (in pQCD) asymmetries in transverse scattering It is now clear that for the comprehensive understanding of the nucleon spin structure any transverse motion of partons in the nucleons is going to be crucial COMPASS, HERMES and Jlab experiments are in hot pursuit of these novel measurements. Anticipated BELLE measurement of polarized fragmentation function are one of the important part of the puzzle. If PHENIX can make a SIGNIFICANT IMPACT on these measurements with LOW run time cost, without derailing the main goals stated above, we think we should make a timely attempt. A short transverse run period in Run-6 presents us with JUST SUCH OPPORTUNITY.
PHENIX Spin Out-Years and HI running 200 GeV Program For RHIC Spin and Heavy Ion physics At RHIC through 2009 Consistent with what We proposed in the Spin Report in February, 2005 • Run-6 • 10 weeks of polarized pp (-5 wks) • 10 weeks of Au-Au (+5 wks) • Run-7 (How long a run???) • 10 weeks of polarized pp (+5 wks) • 10 weeks of d-Au (+??) • Run-8 (How long a run???) • 10 weeks of polarized pp (+??) • 10 weeks of Au-Au (??) • Run-9 (How long a run???) • 5 weeks 200 GeV polarized pp • 5 weeks 500 GeV polarized pp • 10 weeks of ???? HI