Status G Section of Whitepaper

J. Sowinski, A. Deshpande, Y. Goto, M. Stratmann,B. Surrow,

W. Vogelsang

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Our charge from Steve

“…should probably include brief updates on present projections of Delta G and transverse spin sensitivities to be attained in the remaining 200 GeV running”

“Will there be sufficient integrated luminosity to attain the desired Delta G sensitivities in photon and photon-jet production? If not, are there alternatives?”

For you in this talk:What is missing?What is too much?Refine the message(s)?

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Only room for the most prominent results

STAR incl. jets PHENIX incl. 0s

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These results from RHIC have had a strong impact on our knowledge of G

Global fit D. de Florian, R. Sassot, M. Stratmann and W. Vogelsang

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Future: Increased statistics for inclusives still have important contributions to make

PHENIX 25 pb-1 P=60%

G=0.15G=0

Add run 9 to G.A. (Run6)/4

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Semi-inclusive channels to map g(x)STAR di-jets 50 pb-1 P=60%

Xmin = 0.08Xmax =0.20

Xmin = 0.08Xmax =0.20

Xmin = 0.13Xmax =0.15

Xmin = 0.08Xmax =0.32

Xmin = 0.04Xmax =0.37

Xmin = 0.03Xmax =0.46

Typical partonic x pT =10 GeV (LO)

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-jets limited in statistics at 50 pb-1 but still could have impact

xgluon resolution in PHENIX greatly improved with vertex tracker

100% eff. - Perfect BG rejection in STAR for -jets. Di-jets hard to beat but strong cross check could be possible.

50 pb-1 P=60%

GSRV

DSSV

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Placeholder for feasibility of -jet statistical precision

STAR MC simulations – hope to still have something by PAC

SMD shower shape bg rejection vs. efficiency

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What about lower xgluon ?

g(x=0.02)/g(x=0.02)~0.05

Central detectorspT=10GeV

FMS -central jetpT=2GeV

Q2 = 10GeV2

FMS -jet correlation for pT=2GeV and estimate significant number of events in 50 pb-1 wrt g(x)/g(x)=0.05

What is g(x)/g(x) allowed to do for x<0.02?500 GeV one option.

Phenix similar possibility with MPC – Central Cal.

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W physics means lots of beam time at 500 GeV.What can we do there for G?Lower x….

The end of this talk but not the work.