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arXiv · 2408.15043

Polaronic neutron in dilute alpha matter: A $p$-wave Bose polaron

Hiroyuki Tajima·Hajime Moriya·Tomoya Naito·Wataru Horiuchi·Eiji Nakano·Kei Iida
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Abstract

We theoretically investigate quasiparticle properties of a neutron immersed in an alpha condensate, which is one of the possible states of dilute symmetric nuclear matter. The resonant $p$-wave neutron-alpha scattering, which plays a crucial role in forming halo nuclei, is considered. This system is similar to a Bose polaron near the $p$-wave Feshbach resonance that can be realized in cold-atomic experiments. Calculating the self-energy within the field-theoretical approach, we give an analytical formula for the effective mass of a polaronic neutron as a function of alpha condensation density. Moreover, two adjacent neutrons in a medium, each of which behaves like a stable polaron having an enhanced effective mass, can form a bound dineutron, with the help of $^1S_0$ neutron-neutron attraction. This is in contrast to the case of the vacuum, where a dineutron is known to be unbound. Our result would be useful for understanding many-body physics in astrophysical environments as well as the formation of multi-nucleon clusters in neutron-halo nuclei.

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Hiroyuki Tajima, Hajime Moriya, Tomoya Naito, Wataru Horiuchi, Eiji Nakano, Kei Iida. 2024-08-27. Polaronic neutron in dilute alpha matter: A $p$-wave Bose polaron. https://doi.org/10.1103/physrevc.111.025802

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