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NN($^1S_0$) pairs in $^3$He and in p$^3$He backward elastic scattering

Yu. N. Uzikov·J. Haidenbauer
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Abstract

It is shown that the shoulder observed in the cross section of $p^3He$ backward elastic scattering at proton beam energies of 0.4 -- 0.7 GeV can be explained by the mechanism of virtual $π$-meson production with a dominant contribution from the subprocesses $pd^*\to ^3$He$ π^0$ and $p(pp)\to^3$He$ π^+$, where $d^*$ denotes the singlet deuteron and the $pp$ pair is in the $^1S_0$ state. At high energies, 1-3 GeV, the mechanism of $np$-pair transfer dominates and probes high-momentum $NN(^1S_0$) correlations in $^3$He.

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Yu. N. Uzikov, J. Haidenbauer. 2003-08-22. NN($^1S_0$) pairs in $^3$He and in p$^3$He backward elastic scattering. https://arxiv.org/abs/nucl-th/0308063

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