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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. - PowerPoint PPT Presentation
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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
04/19/23 2
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
04/19/23 3
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)
Pai
r tr
igg
er (H
CL
>14
00).
(E
CR
>th
rE)
HCL>4000 (jet trigger)
HCR>4000 (jet trigger)
As expected from simulations, pair trigger enables substantially lower threshold than jet trigger
04/19/23 404/19/23 4
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 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.
~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
04/19/23 5
• 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
04/19/23 5
Conclusions and Plans
04/19/23 704/19/23 7
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
04/19/23 804/19/23 8
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.
04/19/23 904/19/23 9
Run11 AN(Jet)
arXiv:1011.2692v1
200GeV
Non-zero jet analyzing power essentially a prerequisite before proceeding to Drell Yan
arXiv:1103.1591 jet AN 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 AN(Jet) measurements before DY
• With ~10/pb & P=50%, AnDY run11 can measure AN(Jet)
04/19/23 10
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
04/19/23 11
Higher Intensity for IP2 Collisions
IP2 collisions have begun <3 hours after physics ON
Minimal impact on STAR,PHENIX
Fri. 8 April
1.501011/bunch
04/19/23 1204/19/23 12
Schematic of detector for Run-11Equipment 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 ,KS…
• Measure hadronic backgrounds to benchmark simulations
• Measure jet analyzing power (Lint~10 / pb, P=50%)
04/19/23 1304/19/23 13
IP2 in January, 2011Run-11 Staging of ANDY
See http://hena.lbl.gov/IP2/Business/status/<date> for pictures of progress
Left/right symmetric HCal
Left/right symmetric ECal
Left/right symmetric preshower
Trigger/DAQ electronics
Blue-facing BBC
Beryllium vacuum pipe