The sigma meson and chiral restoration in the hot and/or dense nuclear matter

Kunihiro, T.
March 2000
AIP Conference Proceedings;2000, Vol. 508 Issue 1, p217
Academic Journal
We first indicated that if the collective modes with the mass 500–700 MeV exists in the I=J=0 channel, various empirical facts in hadron physics can be naturally accounted for, which otherwise would remain mysterious. We proposed several experiments to produce and detect the σ in nuclei using nuclear and electro-magnetic projectiles. An emphasice was put on the fact that the proper quantity is the spectral function which describes the nuclear medium having a hadron. The recent CHAOS data which show a spectral enhancement near the 2m[sub π] threshold in the σ channel from the reactions A(π,2π)A[sup ′] where A and A[sup ′] denotes nuclei is interpreted as a possible evidence of a partial restoration of chiral symmetry in nuclei. Comments on conventional manybody-theoretical approaches on the experiments were also given. Experiments using nuclear targets were proposed to explore the underlying mechanism of the enhancement seen in the CHAOS experiment. © 2000 American Institute of Physics.


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