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The spectral function of the omega meson in nuclear matter from a coupled-channel resonance model

P. Muehlich·V. Shklyar·S. Leupold·U. Mosel·M. Post
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Abstract

We calculate the spectral function of the omega meson in nuclear matter at zero temperature by means of the low-density theorem. The omega N forward scattering amplitude is calculated within a unitary coupled-channel effective Lagrangian model that has been applied successfully to the combined analysis of pion- and photon-induced reactions. While the peak of the omega spectral distribution is shifted only slightly, we find a considerable broadening of the omega meson due to resonance-hole excitations. For omega mesons at rest with respect to the surrounding nuclear medium, we find an additional width of about 60 MeV at saturation density.

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P. Muehlich, V. Shklyar, S. Leupold, U. Mosel, M. Post. 2006-10-25. The spectral function of the omega meson in nuclear matter from a coupled-channel resonance model. https://doi.org/10.1016/j.nuclphysa.2006.10.037

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