dorsal/arxiv
View SchemaRole of heavy-meson exchange in pion production near threshold
| Authors | C. J. Horowitz, H. O. Meyer, D. Griegel |
|---|---|
| Categories | |
| ArXiv ID | nucl-th/9304004 |
| URL | https://arxiv.org/abs/nucl-th/9304004 |
| DOI | 10.1103/PhysRevC.49.1337 |
| Journal | Phys.Rev.C49:1337-1346,1994 |
Abstract
Recent calculations of $s$-wave pion production have severely underestimated the accurately known $pp\rightarrow pp\pi^0$\ total cross section near threshold. In these calculations, only the single-nucleon axial-charge operator is considered. We have calculated, in addition to the one-body term, the two-body contributions to this reaction that arise from the exchange of mesons. We find that the inclusion of the scalar $\sigma$-meson exchange current (and lesser contributions from other mesons) increases the cross section by about a factor of five, and leads to excellent agreement with the data. The results are neither very sensitive to changes in the distorting potential that generates the $NN$ wave function, nor to different choices for the meson-nucleon form factors. We argue that $pp\rightarrow pp\pi^0$\ data provide direct experimental evidence for meson-exchange contributions to the axial current.
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"abstract": "Recent calculations of $s$-wave pion production have severely underestimated\nthe accurately known $pp\\rightarrow pp\\pi^0$\\ total cross section near\nthreshold. In these calculations, only the single-nucleon axial-charge operator\nis considered. We have calculated, in addition to the one-body term, the\ntwo-body contributions to this reaction that arise from the exchange of mesons.\nWe find that the inclusion of the scalar $\\sigma$-meson exchange current (and\nlesser contributions from other mesons) increases the cross section by about a\nfactor of five, and leads to excellent agreement with the data. The results are\nneither very sensitive to changes in the distorting potential that generates\nthe $NN$ wave function, nor to different choices for the meson-nucleon form\nfactors. We argue that $pp\\rightarrow pp\\pi^0$\\ data provide direct\nexperimental evidence for meson-exchange contributions to the axial current.",
"arxiv_id": "nucl-th/9304004",
"authors": [
"C. J. Horowitz",
"H. O. Meyer",
"D. Griegel"
],
"categories": [
"nucl-th"
],
"doi": "10.1103/PhysRevC.49.1337",
"journal_ref": "Phys.Rev.C49:1337-1346,1994",
"title": "Role of heavy-meson exchange in pion production near threshold",
"url": "https://arxiv.org/abs/nucl-th/9304004"
},
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