# Selective decay from a candidate of the $\sigma$-bond linear-chain state in $^{14}$C

## TL;DR

This study investigates high-lying states in carbon-14 using a cluster-transfer reaction, revealing decay patterns consistent with predicted sigma-bond linear-chain molecular states, including the identification of new resonant states.

## Contribution

The paper reports the experimental observation of high-lying states in $^{14}$C and provides evidence supporting the existence of sigma-bond linear-chain molecular states, including the discovery of new resonant states.

## Key findings

- Identification of a state at 22.5 MeV decaying into 6 MeV states in $^{10}$Be.
- Discovery of a new state at 23.5 MeV decaying into the first excited state of $^{10}$Be.
- Experimental support for the predicted sigma-bond linear-chain molecular states in $^{14}$C.

## Abstract

A cluster-transfer experiment $^9$Be($^9$Be,$^{14}$C$^*\rightarrow\alpha$+$^{10}$Be)$\alpha$ was carried out using an incident beam energy of 45 MeV. This reaction channel has a large $Q$-value that favors populating the high-lying states in $^{14}$C and separating various reaction channels. A number of resonant states are reconstructed from the forward emitting $^{10}$Be + $\alpha$ fragments with respect to three sets of well discriminated final states in $^{10}$Be, most of which agree with the previous observations. A state at 22.5(1) MeV in $^{14}$C is found to decay predominantly into the states around 6 MeV in $^{10}$Be daughter nucleus, in line with the unique property of the predicted band head of the $\sigma$-bond linear-chain molecular states. A new state at 23.5(1) MeV is identified which decays strongly into the first excited state of $^{10}$Be.