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Chiral crossover transition from the Dyson-Schwinger equations in a sphere

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 نشر من قبل Hong-Shi Zong
 تاريخ النشر 2020
  مجال البحث
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Within the framework of Dyson--Schwinger equations of QCD, we study the effect of finite volume on the chiral phase transition in a sphere with the MIT boundary condition. We find that the chiral quark condensate $langlebar{psi} psirangle$ and pseudotransition temperature $T_{pc}$ of the crossover decreases as the volume decreases, until there is no chiral crossover transition at last. We find that the system for $R = infty $ fm is indistinguishable from $R=10$ fm and there is a significant decrease in $T_{pc}$ with $R$ as $R<4$ fm. When $R<1.5$ fm, there is no chiral transition in the system.



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