Hypernuclear cluster states of BΛ12 unveiled through neural network-driven microscopic calculation

Abstract

We investigate the hypernuclear cluster states of ${}_{\Lambda }{}^{12}B$ using a neural-network-driven microscopic model. We extend the Control Neural Networks (Ctrl.NN) method and systematically calculate the positive-parity spectrum of ${}_{\Lambda }{}^{12}B$. By incorporating sd-shell excitations and parity-coupling effects into the ${}_{\Lambda }{}^{12}B$ hypernuclear system, we reveal structural changes, including clustering effects and new configurations such as isosceles-triangle and α-t-α linear-chain structures. Furthermore, by comparing with experimental data, we identify that many peaks (#6 and #8) can be interpreted as $p_{\Lambda }$ dominant states, which is consistent with shell-model predictions. Notably, based on our analysis of the excited states of ${}_{\Lambda }{}^{12}B$, we propose possible candidates for previously unexplained or controversial experimental peaks.