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

L.C.Bland, for AnDY

1 March 2011

Time Meeting, BNL

04/20/23 2

Present Physics Trigger Suite• “minimum bias” – defined as (QB > Q0)(QY > Q0)

• “jet” – defined as (masked HCL > QH)+(masked HCR > QH)

• initial masking excluded column=1 from 12 February

• new masking excludes columns=1,2 and gives no deadtime from 1 March

• “” – defined as (ECL > QE)+(ECR > QE)

• first commissioned on 1 March

• still requires final gain calibration and masking for optimization

• More to come… (HCal high-tower in development stage; ZDC local polarimetry; etc.)

Trigger suite will evaluate backgrounds relevant for Drell Yan and enable

measurement of jet analyzing power.

04/20/23 3

MB Trigger• Minimally biased view of

HCal and ECal

• DAQ rate of ~2.3 kHz samples only portion of luminosity

04/20/23 4

jet Trigger• New definition of jet trigger

excludes both columns 1,2 from sum

• Jet trigger biases Blue-facing BBC to larger charge, since HCal faces same beam

• Collision requirement imposes small additional bias

• Jet trigger hardens ECal response.

LED

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Trigger• trigger selects events with

ECal module sum above threshold (~20 GeV, with present gain calibration)

• trigger gives bias similar to jet trigger for Blue-facing BBC, since ECal faces same beam

• Collision requirement imposes small additional bias

• trigger hardens the Jet trigger response.

LED

04/20/23 6

Triggered Events

Patterns suggest neutral pion accompanied by large energy deposition in corresponding HCal module, as expected for charged decay. Event reconstruction will facilitate determining energy scale for HCal.

04/20/23 7

Accounting• Thanks to Tom Throwe, we are

storing CDEV information into mysql data base.

• Thanks to Akio Ogawa, we have begun tracking integrated luminosity at IP2, since jet trigger was first commissioned

• Presently, no accidentals correction (to be fixed in next access)

• Require vernier scan to establish effective cross section.

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

04/20/23 8

Issues and Plansfor next access possibility and beyond

• Resolve a few remaining single-channel issues

• Reduce HCal gain – limited scheduled access time last Wednesday did not allow completion of HCal gain reduction.

We are in “production” with a jet trigger >200M jet events recorded.

In coming week…

• Reduce HCal gain

• Complete ECal gain matching

• Increase per bunch intensity for IP2 bump removal

• Remove beam crossing angle at IP2

04/20/23 9

Backup

04/20/23 10

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 11

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