Preliminary Results on Direct Photon-Photon HBT Measurements in $\sqrt{s_{\rm{NN}}}$ = 62.4 GeV and 200 GeV Au+Au Collisions at RHIC

Debasish Das; Guoji Lin; Subhasis Chattopadhyay; Alexei Chikanian; Evan Finch; Tapan K Nayak; Sergey Y Panitkin; Jack Sandweiss; Alexandre Alarcon Suaide; Haibin Zhang

arXiv · nucl-ex/0511055

Preliminary Results on Direct Photon-Photon HBT Measurements in $\sqrt{s_{\rm{NN}}}$ = 62.4 GeV and 200 GeV Au+Au Collisions at RHIC

Debasish Das·Guoji Lin·Subhasis Chattopadhyay·Alexei Chikanian·Evan Finch·Tapan K Nayak·Sergey Y Panitkin·Jack Sandweiss·Alexandre Alarcon Suaide·Haibin Zhang

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Abstract

We present the preliminary results on direct photon interferometry measurements in Au+Au collisions at $\sqrt{s_{\rm{NN}}}$ = 62.4 and 200 GeV using the STAR (Solenoidal Tracker at RHIC) detector. Photons are reconstructed via $e^+/e^-$ conversions in STAR Time Projection Chamber(TPC) and energy deposited by photons in STAR Barrel Electromagnetic Calorimeter(BEMC). The two-photon correlations are measured using (1) both photons measured using BEMC; (2) one photon from conversions and the other measured with BEMC. Both the methodologies and the possible constraints in the correlation function measurements are discussed.

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Debasish Das, Guoji Lin, Subhasis Chattopadhyay, Alexei Chikanian, Evan Finch, Tapan K Nayak, Sergey Y Panitkin, Jack Sandweiss, Alexandre Alarcon Suaide, Haibin Zhang. 2005-11-30. Preliminary Results on Direct Photon-Photon HBT Measurements in $\sqrt{s_{\rm{NN}}}$ = 62.4 GeV and 200 GeV Au+Au Collisions at RHIC. https://arxiv.org/abs/nucl-ex/0511055

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