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System size dependence of transverse momentum correlations at $sqrt{s_{NN}}=$ 62.4 and 200 GeV at the BNL Relativistic Heavy Ion Collider

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 نشر من قبل Lokesh Kumar
 تاريخ النشر 2013
  مجال البحث
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We present a study of the average transverse momentum ($p_t$) fluctuations and $p_t$ correlations for charged particles produced in Cu+Cu collisions at midrapidity for $sqrt{s_{NN}} =$ 62.4 and 200 GeV. These results are compared with those published for Au+Au collisions at the same energies, to explore the system size dependence. In addition to the collision energy and system size dependence, the $p_t$ correlation results have been studied as functions of the collision centralities, the ranges in $p_t$, the pseudorapidity $eta$, and the azimuthal angle $phi$. The square root of the measured $p_t$ correlations when scaled by mean $p_t$ is found to be independent of both colliding beam energy and system size studied. Transport-based model calculations are found to have a better quantitative agreement with the measurements compared to models which incorporate only jetlike correlations.



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