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Current algebra and soft pionic modes in asymmetric quark matter

Wojciech Broniowski·Brigitte Hiller
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Abstract

Pionic excitations are analyzed in isospin-asymmetric Fermi gas of constituent quarks. It is found that in addition to the usual pionic excitations, there exists a very low collective mode with quantum numbers of the charged pion (spin-isospin sound). In the chiral limit the excitation energy of one of the modes scales as the current quark mass, and the mode saturates current-algebraic sum rules. This is in agreement with predictions of current algebra for isospin-asymmetric medium.

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Wojciech Broniowski, Brigitte Hiller. 1996-11-27. Current algebra and soft pionic modes in asymmetric quark matter. https://doi.org/10.1016/s0370-2693(96)01551-1

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