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Chiral phase transition in relativistic heavy-ion collisions with weak magnetic fields: ring diagrams in the linear sigma model

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 نشر من قبل Angel Sanchez Dr
 تاريخ النشر 2009
  مجال البحث
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Working in the linear sigma model with quarks, we compute the finite-temperature effective potential in the presence of a weak magnetic field, including the contribution of the pion ring diagrams and considering the sigma as a classical field. In the approximation where the pion self-energy is computed perturbatively, we show that there is a region of the parameter space where the effect of the ring diagrams is to preclude the phase transition from happening. Inclusion of the magnetic field has small effects that however become more important as the system evolves to the lowest temperatures allowed in the analysis.



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