A N DY Status Commissioning with colliding beams (p  +p  at s=500 GeV)

ANDY StatusCommissioning with colliding beams (p+p at s=500 GeV) L.C.Bland, for AnDY 1 March 2011 Time Meeting, BNL

Present Physics Trigger Suite • “minimum bias” – defined as (SQB > Q0)(SQY > Q0) • “jet” – defined as (masked SHCL > QH)+(masked SHCR > QH) • initial masking excluded column=1 from 12 February • new masking excludes columns=1,2 and gives no deadtime from 1 March • “p0” – defined as (SECL > QE)+(SECR > 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.

MB Trigger • Minimally biased view of HCal and ECal • DAQ rate of ~2.3 kHz samples only portion of luminosity

LED 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 p0 Trigger • p0 trigger selects events with ECal module sum above threshold (~20 GeV, with present gain calibration) • p0 trigger gives bias similar to jet trigger for Blue-facing BBC, since ECal faces same beam • Collision requirement imposes small additional bias • p0 trigger hardens the Jet trigger response.

p0 Triggered Events Patterns suggest neutral pion accompanied by large energy deposition in corresponding HCal module, as expected for charged r decay. Event reconstruction will facilitate determining energy scale for HCal.

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.

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

Backup

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%)

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 See http://hena.lbl.gov/IP2/Business/status/<date> for pictures of progress

A N DY Status Commissioning with colliding beams (p  +p  at s=500 GeV)