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Formation and decay of hadronic resonances in the QGP

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 نشر من قبل Christina Markert
 تاريخ النشر 2008
  مجال البحث
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Hadronic resonances can play a pivotal role in providing experimental evidence for partial chiral symmetry restoration in the deconfined quark-gluon phase produced at RHIC. Their lifetimes, which are comparable to the lifetime of the partonic plasma phase, make them an invaluable tool to study medium modifications to the resonant state due to the chiral transition. In this paper we show that the heavier, but still abundant, light and strange quark resonances K*, phi, Delta and Lambda* have large probability to be produced well within the plasma phase due to their short formation times. We demonstrate that, under particular kinematic conditions, these resonances can be formed and will decay inside the partonic state, but still carry sufficient momentum to not interact strongly with the hadronic medium after the QCD phase transition. Thus, K*, phi, Delta and Lambda* should exhibit the characteristic property modifications which can be attributed to chiral symmetry restoration, such as mass shifts, width broadening or branching ratio modifications.



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