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Double Longitudinal Spin Asymmetry in Neutral Pion Production in Polarized p+p Collisions at sqrt(s)=200 GeV at PHENIX

Kieran Boyle
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Abstract

A major goal of the RHIC spin program is to measure Δg, the gluon contribution to the proton's spin. Measurements by PHENIX of the double longitudinal spin asymmetry, A_LL, of the neutral pion production at mid-rapidity in polarized proton collisions have been shown to constrain Δg. Results from the 2005 RHIC run, as well as high p_T data from the 2006 RHIC run, are presented. The results disfavor maximal positive and negative values of Δg. A measurement of azimuthally independent double transverse spin asymmetry, A_TT, is also presented.

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Kieran Boyle. 2007-01-26. Double Longitudinal Spin Asymmetry in Neutral Pion Production in Polarized p+p Collisions at sqrt(s)=200 GeV at PHENIX. https://doi.org/10.1063/1.2750790

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