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arXiv · 1411.7863

Wilson coefficients and four-quark condensates in QCD sum rules for medium modifications of $D$ mesons

Thomas Buchheim·Thomas Hilger·Burkhard Kampfer
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Abstract

Wilson coefficients of light four-quark condensates in QCD sum rules are evaluated for pseudo-scalar $D$ mesons, thus, pushing the sum rules toward mass dimension six. Contrary to the situation for $\bar{q}q$ mesons the impact of the four-quark condensates for vacuum as well as in-medium situations is found to be rather small within the Borel window used in previous analyses. The complete four-quark condensate contributions enable to identify candidates for an order parameter of spontaneous chiral symmetry breaking/restoration as well as to evaluate stability criteria of operator product expansions.

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Thomas Buchheim, Thomas Hilger, Burkhard Kampfer. 2014-11-28. Wilson coefficients and four-quark condensates in QCD sum rules for medium modifications of $D$ mesons. https://doi.org/10.1103/physrevc.91.015205

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