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Mid-Rapidity Direct-Photon Production in p+p Collisions at sqrt(s) = 200 GeV

PHENIX Collaboration·S. Adler
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Abstract

A measurement of direct photons in p+p collisions at sqrt(s)=200 GeV is presented. A photon excess above background from pi^0 --> gamma+gamma, eta --> gamma+gamma, and other decays is observed in the transverse momentum range 5.5 < p_T < 7 GeV/c. The result is compared to a next-to-leading-order perturbative QCD calculation. Within errors, good agreement is found between the QCD calculation and the measured result.

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PHENIX Collaboration, S. Adler. 2005-02-02. Mid-Rapidity Direct-Photon Production in p+p Collisions at sqrt(s) = 200 GeV. https://doi.org/10.1103/physrevd.71.071102

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