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A N DY Status Commissioning with colliding beams (p +p at s=500 GeV). L.C.Bland, for AnDY 19 April 2011 Time Meeting, BNL. Local Polarimetry Tuned parameters for scaler board.
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ANDY StatusCommissioning with colliding beams (p+p at s=500 GeV) L.C.Bland, for AnDY 19 April 2011 Time Meeting, BNL
Local PolarimetryTuned parameters for scaler board • Gain-matching of ZDC shower maximum detector (SMD) derived from event analysis has been implemented for the scaler board measurements • An effective threshold on ZDC SMD energy deposition is applied to the scaler board data • Scaler board data for local polarimetry was acquired with final parameters for fill>15465 • Analysis of scaler board data is underway
SHCR>4000 (jet trigger) SHCR>4000 (jet trigger) SHCL>4000 (jet trigger) SHCL>4000 (jet trigger) Pair trigger (SHCL>1400).(SHCR>1400) Pair trigger (SHCR>1400).(SECL>thrE) Pair trigger (SHCL>1400).(SECR>thrE) Pair Trigger • Drell-Yan will result in correlated response of left and right detector arms • Jet trigger does not span full space of pair correlations • A pair trigger was implemented and used for data recorded for fill>15465 • Converter plates were installed on 15 April, as needed for e/h discrimination As expected from simulations, pair trigger enables substantially lower threshold than jet trigger
Integrated Luminosity Estimate to Date ~1.6mr crossing angle ~0mr crossing angle systematically increased thresholds for IP2 collisions ~2mr crossing angle • Presently, no accidentals correction (found to be large for ZDC). All rates are now scaled on bunch-crossing scalers, following 20110330 access and subsequent timing adjustments. • Requires calibration of effective cross section for BBC via vernier scan. • Need to reconcile assumptions about cross sections against vernier scan measurements in fill=15457 • Jet analyzing power measurement sets goal of 10 / pb for run 11. Many thanks to C-A for increasing the threshold for IP2 collisions 12/1/2014 4
Conclusions and Plans • Repeated fills have demonstrated that IP2 collisions can have minimal impact on IP6,IP8 luminosity • With decreased b* and ~10 hour stores, run-11 has demonstrated that 15 / pb / week can be delivered to IP2 in runs 12,13 • Comparison of run-11 data to simulation is underway • We will proceed with a proposal to the 2011 PAC • >750M jet trigger events recorded in run 11 12/1/2014 5
Backup 12/1/2014 6
Reminder of GoalsLong-term and run-11 • Goals of ANDY project: • Establish that large-xF low-mass dileptons from the Drell-Yan process can be discriminated from background in s=500 GeV p+p collisions • Measure the analyzing power for Drell-Yan production with sufficient statistical precision to test the theoretical prediction of a sign change for DY in relation to semi-inclusive deep inelastic scattering • Establish if robust detection of Drell-Yan dileptons at large xF and low mass requires magnetic analysis critical for future facilities at RHIC 12/1/2014 7
ANDY Prioritiesfor remainder of RHIC run-11 • Run-11 goals: • Establish the impact of a third IR on RHIC performance for p+p collisions at s=500 GeV - Demonstrate luminosity at IP2, as required for Drell-Yan sample in runs 12 (without magnet),13 (with magnet). Estimate that 150 / pb gives 104 large-rapidity di-electrons with M>4 GeV/c2 for p+p at s=500 GeV. Is this possible in a 10-week run? • Demonstrate calibration of HCal • Measure analyzing power for large xF jet production. Non-zero AN required for jets if Drell-Yan production has an analyzing power. Complete the measurement of the analyzing power for jet production. A non-zero AN for jets is a requirement for Drell-Yan to have non-zero analyzing power. Recent theoretical work establishes intrinsic interest in the jet analyzing power measurement. 12/1/2014 8
Run11 AN(Jet) arXiv:1103.1591 jet AN measurements are required to clarify signs of quark/gluon correlators related to Sivers functions. arXiv:1011.2692v1 s=200 GeV from p+pp “new” Sivers function “old” Sivers function 200GeV Non-zero jet analyzing power essentially a prerequisite before proceeding to Drell Yan 12/1/2014 • Siver’s effect only (no collin’s effect contribution) • Need AN(Jet) measurements before DY • With ~10/pb & P=50%, AnDY run11 can measure AN(Jet) 9
Estimates • At present threshold for IP2 collisions (average intensity < 0.901011/bunch), integrate ~200 / nb / fill • 2 fills/day has been achieved • Consequently, 12.5 days are required to get 5 / pb • Maximum possible integrated luminosity (IP2 collisions for entire fill) would yield ~700 nb/fill • One week at 2 fills/day would provide 5 / pb • Two weeks at 2 fills/day would provide 10 / pb
Minimal impact on STAR,PHENIX Higher Intensity for IP2 Collisions Fri. 8 April 1.501011/bunch IP2 collisions have begun <3 hours after physics ON
Schematic of detector for Run-11 • Equipment in place: • HCal is two existing 9x12 modules from E864 (NIM406,227) • ECal are two small lead-glass modules from BigCal at JLab • BBC (from PHOBOS) and ZDC • Preshower is newly constructed scintillator arrays • Goals: • Establish impact of 3IR operation on PHENIX/STAR luminosity • Calibrate HCal • relative gain via cosmic-ray m • absolute energy scale via r,L,KS… • Measure hadronic backgrounds to benchmark simulations • Measure jet analyzing power (Lint~10 / pb, P=50%) 12/1/2014 12
Trigger/DAQ electronics Left/right symmetric HCal Left/right symmetric ECal Blue-facing BBC Left/right symmetric preshower Beryllium vacuum pipe IP2 in January, 2011Run-11 Staging of ANDY 12/1/2014 13 See http://hena.lbl.gov/IP2/Business/status/<date> for pictures of progress