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Spectral Red-Shift Versus Broadening from Photon and Dilepton Spectra

Jan-e Alam·Pradip Roy·Sourav Sarkar·Bikash Sinha
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Abstract

We estimate the photon and dilepton emission rates from hot hadronic matter with in-medium spectral shift and broadening of vector mesons. It is observed that both the WA98 photon data and CERES/NA45 dilepton data can be well reproduced with similar initial conditions. The freeze-out condition has been constrained by the transverse mass spectra of pions and protons measured by the NA49 collaboration. We argue that simultaneous measurement of the $p_T$ spectra of single photons as well as invariant mass distribution of dileptons is crucial to understand the in-medium spectral function of the vector mesons.

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Jan-e Alam, Pradip Roy, Sourav Sarkar, Bikash Sinha. 2003-01-10. Spectral Red-Shift Versus Broadening from Photon and Dilepton Spectra. https://doi.org/10.1103/physrevc.67.054901

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