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

6/23/20162 Local Polarimetry Tuned 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

6/23/20163  HCL>4000 (jet trigger)  HCR>4000 (jet 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 Pair Trigger Pair trigger (  HCL>1400).(  HCR>1400) Pair trigger (  HCR>1400).(  ECL>thrE) Pair trigger (  HCL>1400).(  ECR>thrE)  HCL>4000 (jet trigger)  HCR>4000 (jet trigger) As expected from simulations, pair trigger enables substantially lower threshold than jet trigger

6/23/ Integrated Luminosity Estimate to Date Presently, no accidentals correction (found to be large for ZDC). All rates are now scaled on bunch-crossing scalers, following 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. ~2mr crossing angle ~1.6mr crossing angle ~0mr crossing angle Many thanks to C-A for increasing the threshold for IP2 collisions systematically increased thresholds for IP2 collisions

6/23/20165 Repeated fills have demonstrated that IP2 collisions can have minimal impact on IP6,IP8 luminosity With decreased  * 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 6/23/20165 Conclusions and Plans

6/23/ Backup

6/23/ Reminder of Goals Long-term and run-11 Goals of A N DY project: Establish that large-x F 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 x F and low mass requires magnetic analysis  critical for future facilities at RHIC

6/23/ A N DY Priorities for 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 10 4 large- rapidity di-electrons with M>4 GeV/c 2 for p+p at  s=500 GeV. Is this possible in a 10- week run? Demonstrate calibration of HCal Measure analyzing power for large x F jet production. Non-zero A N required for jets if Drell-Yan production has an analyzing power. Complete the measurement of the analyzing power for jet production. A non-zero A N 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.

6/23/ Run11 A N (Jet) arXiv: v1 200GeV Non-zero jet analyzing power essentially a prerequisite before proceeding to Drell Yan arXiv: jet A N measurements are required to clarify signs of quark/gluon correlators related to Sivers functions. from p  +p  “old” Sivers function “new” Sivers function  s=200 GeV Siver’s effect only (no collin’s effect contribution) Need A N (Jet) measurements before DY With ~10/pb & P=50%, AnDY run11 can measure A N (Jet)

6/23/ Estimates At present threshold for IP2 collisions (average intensity < 0.90  /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

6/23/ Higher Intensity for IP2 Collisions IP2 collisions have begun <3 hours after physics ON Minimal impact on STAR,PHENIX Fri. 8 April 1.50  /bunch

6/23/ /23/ 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  absolute energy scale via ,K S … Measure hadronic backgrounds to benchmark simulations Measure jet analyzing power (L int ~10 / pb, P=50%)

6/23/ /23/ IP2 in January, 2011 Run-11 Staging of A N DY See for pictures of progresshttp://hena.lbl.gov/IP2/Business/status/<date Left/right symmetric HCal Left/right symmetric ECal Left/right symmetric preshower Trigger/DAQ electronics Blue-facing BBC Beryllium vacuum pipe