Significance of the Sigma Meson in Hadron Physics (QCD) and Possible Experiments to Observe it
Abstract
We first discuss the theoretical and phenomenological significance of the sigma meson ($\sigma$) in QCD. It is indicated that if the collective modes with the mass 500-600 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 propose several experiments to produce and detect the $\sigma$ in nuclei using nuclear and electro-magnetic projectiles. The recent CHAOS data which show a spectral enhancement near the 2 $m_{\pi}$ threshold in the $\sigma$ channel from the reactions A$(\pi, 2\pi)$A' where A and A' denotes nuclei is interpreted as a possible evidence of a partial restoration of chiral symmetry in nuclei.
- Publication:
-
arXiv e-prints
- Pub Date:
- May 1999
- DOI:
- 10.48550/arXiv.hep-ph/9905262
- arXiv:
- arXiv:hep-ph/9905262
- Bibcode:
- 1999hep.ph....5262K
- Keywords:
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- High Energy Physics - Phenomenology;
- High Energy Physics - Experiment;
- Nuclear Experiment;
- Nuclear Theory
- E-Print:
- Invited talk presented at the Workshop on Hadron Spectroscopy (whs99), Frascati- INFN, March 8 - 12, 1999. 8 pages with one figure