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arXiv · 0905.3119

Heavy-baryon chiral perturbation theory approach to thermal neutron capture on ${}^{3}{He}$

Rimantas Lazauskas·Young-Ho Song·Tae-Sun Park
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Abstract

The cross section for radiative thermal neutron capture on ${}^{3}He$ ($\He3 +n \to \He4 +\gamma$; known as the $hen$ reaction) is calculated based on heavy-baryon chiral perturbation theory. The relevant M1 operators are derived up to next-to-next-to-next-to-leading order (N${}^3$LO). The initial and final nuclear wave functions are obtained from the rigorous Faddeev-Yakubovski equations for five sets of realistic nuclear interactions. Up to N${}^3$LO, the M1 operators contain two low-energy constants, which appear as the coefficients of non-derivative two-nucleon contact terms. After determining these two constants using the experimental values of the magnetic moments of the triton and ${}^3 He$, we carry out a parameter-free calculation of the $hen$ cross section. The results are in good agreement with the data.

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Rimantas Lazauskas, Young-Ho Song, Tae-Sun Park. 2009-05-19. Heavy-baryon chiral perturbation theory approach to thermal neutron capture on ${}^{3}{He}$. https://doi.org/10.1103/physrevc.83.034006 10.1103/physrevc.83.049901

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