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arXiv · 1110.2242

A direct probe of the in-medium pn scattering cross section

Gao-Chan Yong·Wei Zuo·Xun-Chao Zhang
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Abstract

Hard photon production from neutron-proton bremsstrahlung in intermediate energy heavy-ion reactions is examined as a probe of the in-medium pn scattering cross section within a transport model. Uncertainty of photon production probability pn-pngamma is cancelled out by using the ratio of hard photon spectra R_{12C+12C/p+n}(gamma) from two reactions. The in medium pn scattering cross section is constrained by using the ratio of hard photon production cross sections of proton-induced reactions p+12C and p+2H. A reduction factor sigma_pn^medium/sigma_pn^free of about 0.5 ~ 0.7 around saturation density is obtained by comparing with the existing experimental data.

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Gao-Chan Yong, Wei Zuo, Xun-Chao Zhang. 2011-10-11. A direct probe of the in-medium pn scattering cross section. https://doi.org/10.1016/j.physletb.2011.10.020

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