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arXiv · 2408.14602

Two-Body Triton Photodisintegration and Wigner-SU(4) Symmetry

Xincheng Lin·Jared Vanasse
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Abstract

We calculate the two-body triton photodisintegration cross section as a function of photon energy to next-to-next-to leading order (NNLO) in pionless effective field theory (EFT($\pi \!\!/$)) and show good agreement with experiment. In addition we calculate the polarization asymmetry $R_C=-0.441(15)$ in cold neutron-deuteron capture to NNLO in EFT($\pi \!\!/$), in agreement with the experimental value of $R_C=-0.42\pm 0.03$ [M. W. Konijnenberg et al. in Phys. Lett. B 205, 215 (1988)]. We also assess the dependence of $R_C$ on different fits of the two-nucleon magnetic currents. Finally, we consider the impact of Wigner-SU(4) symmetry and demonstrate that starting from the Wigner-SU(4) symmetric limit and including perturbative corrections to the breaking of Wigner-SU(4) symmetry does a good job of describing two-body triton photodisintegration.

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Xincheng Lin, Jared Vanasse. 2024-08-26. Two-Body Triton Photodisintegration and Wigner-SU(4) Symmetry. https://doi.org/10.1103/qgcx-r63r

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