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arXiv · 0711.4145

Measurement of photons via conversion pairs in Au+Au collisions at sqrt(s_NN) = 200 GeV with the PHENIX experiment at RHIC

Torsten Dahms
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Abstract

Thermal photons can provide information on the temperature of the new state of matter created at RHIC. In the p_T region of 1--3 GeV/c thermal photons are expected to be the dominant direct photon source. Therefore, a possible excess compared to a pure decay photon signal due to a thermal photon contribution should be seen in the double ratio (gamma/gamma(pi^0))_{Measured}/(gamma/gamma(pi^0))_{Simulated}, if sufficient accuracy can be reached. We present a method to reconstruct direct photons by measuring e^+e^- pairs from external photon conversions.

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Torsten Dahms. 2007-11-26. Measurement of photons via conversion pairs in Au+Au collisions at sqrt(s_NN) = 200 GeV with the PHENIX experiment at RHIC. https://arxiv.org/abs/0711.4145

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