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Transport Coefficient to Trace Anomaly in the Clustering of Color Sources Approach

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 نشر من قبل Brijesh K. Srivastava
 تاريخ النشر 2016
  مجال البحث
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From our previously obtained shear viscosity to entropy density ratio ($eta/s$) in the framework of clustering of color sources (Color String Percolation Model: CSPM), we calculate the jet quenching parameter $hat {q}$ and trace anomaly $Delta = (varepsilon -3it p)/T^{4}$ as a function of temperature. It is shown that the scaled $hat {q}/T^{3}$ is in agreement with the recent JET Collaboration estimates. The inverse of $eta/s$ is found to represent $Delta$. The results for $Delta$ are in excellent agreement with Lattice Quantum Chromo Dynamics (LQCD) simulations. From the trace anomaly and energy density $epsilon$, the equation of state is obtained as a function of temperature and compared with LQCD simulations. It is possible that there is a direct connection between the $eta/s$ and $Delta$. Thus the estimate of transport coefficient $eta/s$ provides $hat {q}$ and $Delta$ as a function of temperature. Both $Delta$ and $eta/s$ describe the transition from a strongly coupled QGP to a weakly coupled QGP.



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