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$^3$He Structure and Mechanisms of $p^3$He Backward Elastic Scattering

Yu. N. Uzikov·J. Haidenbauer
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Abstract

The mechanism of $p^3$He backward elastic scattering is studied. It is found that the triangle diagrams with the subprocesses $pd\to ^3$He$ π^0$, $pd^*\to ^3$He$ π^0$ and $p(pp)\to^3$He$ π^+$, where $d^*$ and $pp$ denote the singlet deuteron and diproton pair in the $^1S_0$ state, respectively, dominate in the cross section at 0.3-0.8 GeV, and their contribution is comparable with that for a sequential transfer of a $np$ pair at 1-1.5 GeV. The contribution of the $d^*+pp$, estimated on the basis of the spectator mechanism of the $p(NN)\to ^3$He$ π$ reaction, increases the $p^3$He$\to ^3$He$ p$ cross section by one order of magnitude as compared to the contribution of the deuteron alone. Effects of the initial and final states interaction are taken into account.

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Yu. N. Uzikov, J. Haidenbauer. 2003-05-23. $^3$He Structure and Mechanisms of $p^3$He Backward Elastic Scattering. https://doi.org/10.1103/physrevc.68.014001

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