Tensor coupling effects on spin symmetry in anti-Lambda spectrum of hypernuclei

TL;DR

This study investigates how tensor coupling influences spin symmetry in anti-Lambda spectra within hypernuclei, revealing that while it significantly increases spin-orbit splittings, the overall spin symmetry remains largely unaffected across various nuclear systems.

Contribution

It demonstrates that tensor coupling greatly enhances spin-orbit splittings without compromising spin symmetry in anti-Lambda hypernuclei, using relativistic mean-field theory across multiple nuclei.

Findings

Tensor coupling increases spin-orbit splittings by an order of magnitude.

Wave functions of anti-Lambda are unaffected by tensor coupling.

Spin symmetry remains robust despite tensor effects.

Abstract

The effects of $\bar\Lambda\bar\Lambda\omega$-tensor coupling on the spin symmetry of $\bar{\Lambda}$ spectra in $\bar{\Lambda}$-nucleus systems have been studied with the relativistic mean-field theory. Taking $^{12}$C+$\bar{\Lambda}$ as an example, it is found that the tensor coupling enlarges the spin-orbit splittings of $\bar\Lambda$ by an order of magnitude although its effects on the wave functions of $\bar{\Lambda}$ are negligible. Similar conclusions has been observed in $\bar{\Lambda}$-nucleus of different mass regions, including $^{16}$O+$\bar{\Lambda}$, $^{40}$Ca+$\bar{\Lambda}$ and $^{208}$Pb+$\bar{\Lambda}$. It indicates that the spin symmetry in anti-lambda-nucleus systems is still good irrespective of the tensor coupling.