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

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.

Comments: 12 pages, 3 figures,