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Vector Meson Propagator and Baryon Current Conservation

S. S. Wu·H. X. Zhang·Y. J. Yao
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Abstract

If baryons couple only with $ω$-mesons, one found the baryon spectral function may be negative. We show this unacceptable result is caused by the $k_μk_ν$-terms in the $ω$-meson propagator. Their contribution may not vanish in approximate calculations which violate the baryon current conserves. A rule is suggested, by which the calculated baryon spectral function is well behaved.

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S. S. Wu, H. X. Zhang, Y. J. Yao. 2001-04-29. Vector Meson Propagator and Baryon Current Conservation. https://doi.org/10.1016/s0370-2693(01)00772-9

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