# Presentation: 925735

## STAR Goals for Run 9

- RHIC Planning meeting

- James Dunlop
- Brookhaven National Laboratory

## Executive Summary of Goals

- Commission major detector upgrades
- Physics and preparation for the future at 500 GeV
- Establish local polarimetry of transverse components
- W cross-section
- W AL:  10 pb-1 sampled, Longitudinal polarization 50%
- pp2pp @ 200 GeV: 1⁄2 week for complete transverse program
- If the run is extended: highest priority 200 GeV p+p
- BUR: 50 pb-1 sampled, 60% Polarization: FOM P4L = 6.5 pb-1
- Needs ~11 weeks for full goal

- 12/8/2008

- RHIC Planning meeting

## First things first: Commissioning

- Major changes in the detector: will need to be commissioned

- 12/8/2008

- RHIC Planning meeting

- Time Projection Chamber DAQ1000: replacement of entire electronics chain

- Time of Flight: 75% of trays in place
- First run with more than ~few trays

- Electromagnetic Calorimeter:
- 	Shower Max: modification of 	electronics to decrease deadtime
- 	Towers: rewire trigger to increase 		jet efficiency

## Primary goals at 500 GeV

- Plan to start with transverse polarization
- Likely needs ~1 week after commissioning, but still in discussion
- Establish local polarimetry
- At 200 GeV: used BBC, does the AN persist to 500 GeV?
- Investigating other methods: ZDC Shower Max, VPD, ...
- Need to measure sizeable asymmetry before rotating to longitudinal as part of establishing local polarimetry
- Low backgrounds necessary for interpretability
- Important for the future: need to know what we need
- Primary physics goal: W
- Observe decay signal, cross-section, aim to separate by charge
- First measurement of AL

- 12/8/2008

- RHIC Planning meeting

## Primary Goal at 500 GeV: W physics

- 12/8/2008

- RHIC Planning meeting

- FOM = 2.5 pb-1
- Polarization = 50%
- Longitudinal
- Luminosity: 10pb-1

- Goal 2: First measurement of AL for W

- Goal 1:  First W cross-section in STAR (using mid-rapidity e)
- 		Effective signal ~250 (W+) ~60 (W-) with 10 pb-1

## Worst Case Luminosity Projections

- Lose ~10 in first weeks, delivered ~40 after 5 weeks = 30 pb-1
- 10 pb-1 sampled should be achievable during longitudinal running
- Would appreciate more if things go well

- 12/8/2008

- RHIC Planning meeting

- Integrated Luminosity [pb-1]

- Weeks in physics

- T

## Other opportunities at 500 GeV

- First measurement of AN at 500 GeV with Forward Pion Detector and Forward Meson Spectrometer
- Jets and dijets: Δg(x) to lower x, different parton subprocesses
- With projected integrated luminosity and polarization: proof-of-principle
- Heavy flavor
- Use the TOF, EMC, and reduced material to measure charm, non-photonic electrons, J/Ψ and Upsilon
- Useful as check on theory
- Dileptons: first from STAR
- Expect significant φee signal with ~100M minbias events

- 12/8/2008

- RHIC Planning meeting

## pp2pp goal at 200 GeV

- 3 1/2 days of running satisfies the transverse program
- √s = 200 GeV
- Transverse polarization
- Instantaneous L = 31029 cm-2sec-1
- β*=20m
- 40 hours data taking will achieve goal

- 12/8/2008

- RHIC Planning meeting

## If Run 9 is extended: 200 GeV

- Significant extension of precision in inclusive jets
- RHIC becomes the dominant constraint

- 12/8/2008

- RHIC Planning meeting

- Goal in the BUR: L = 50 pb-1,P= 60% : FOM 6.5 pb-1

## Dijets at 200 GeV

- Goal in the BUR: L = 50 pb-1,P= 60% : FOM 6.5 pb-1

- 12/8/2008

- RHIC Planning meeting

- Shape of Δg(x) not strongly constrained by RHIC inclusive data alone
- Probe x dependence of  Δg(x) using kinematic constraints provided by dijets

## Goals from p+p 200 GeV for heavy ion physics

- Reference for Au in RHIC II era: last chance for a few years

- 12/8/2008

- RHIC Planning meeting

- Goal in the BUR: L = 50 pb-1

- Factor 5x increase in L for rare probes vs. run 6
-  Non-photonic electrons: extend correlation signatures for B vs. D
-  J/Ψ: use TOF and EMC for precision
-  Upsilon: 1st attempt to separate higher states
-  γ-hadron: currently p+p is limit on IAA
- Large minbias dataset with DAQ1000: 300 M
- Has not been possible in previous years, due to DAQ limitations
- Fundamental baseline for untriggerable probes: D, dileptons, hadrons