ANDY StatusCommissioning with colliding beams (p+p at s=500 GeV)

L.C.Bland, for AnDY

8 March 2011

Time Meeting, BNL

04/20/23 2

Gain Monitoring for Hadron Calorimeter• Fast current pulser (from Berkeley)

and Blue Nichia light-emitting diodes (LED) drive fiber optics to distribute fast light pulses to individual detectors.

• Used LED system to measure gain curves from each HCal PMT prior to start of run 11.

• Use LED system as continuous gain monitor for cosmic rays and collisions.

g=g0(V/V0)a

04/20/23 3

HCal Gain ChangeDuring 20110302 Access

• Gain adjustment to enable jet physics to large xF at s=500 GeV

• Choose target to be 60% of gain used for day<11061 jet trigger.

• Used measured gain curves for each PMT.

• Confirmed gain change with LED system.

04/20/23 4

Effect of HCal Gain Change

Before Gain Change After Gain Change

Ready for jet physics to large xF at s = 500 GeV

107 ns before trigger

107 ns after trigger

04/20/23 5

ZDC Response

• ZDC response (summed over three modules) to different triggers shows interesting biases.

• ZDC trigger is still required to be commissioned for local polarimetry

• ZDC shower maximum detector is mostly in working order.

04/20/23 6

ZDC Shower Maximum Detectorjet trigger

Blue vertical strips

Blue horizontal strips

Yellow vertical strips

Yellow horizontal strips

04/20/23 7

ZDC SMD Events• Select events that have

Q>250 and Q2>10 (middle module) for Yellow-facing ZDC

• Make event display by having vertical axis correspond to ADC value and horizontal axis correspond to detector ID.

• Showers look reasonable; double checks of mapping still required

• Next step is to trigger on ZDC for local polarimetry, using bunch counter to distinguish single-beam backgrounds from collisions.

04/20/23 8

Integrated Luminosity Estimate to Date

• Presently, no accidentals correction (found to be large for ZDC). Singles rates from BBC are now scaled, following 20110302 access.

• Requires calibration of effective cross section for BBC via vernier scan.

• Jet analyzing power measurement sets goal of 10 / pb for run 11.

• Establishing luminosity capability in run 11 is important for Drell Yan attempt in runs 12,13 (150 / pb in each run)

04/20/23 9

Issues and PlansIssues

• Resolve a few remaining single-channel issues

We are in “production” with a jet trigger >250M jet events recorded.

In coming week…

• Complete ECal gain matching

• Commission ZDC trigger for local polarimetry.

• Commission scaler system for local polarimetry.

• Increase per bunch intensity for IP2 bump removal?

• Remove beam crossing angle at IP2?

04/20/23 10

Backup

04/20/23 11

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%)

04/20/23 12

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