Characteristic \alpha and ^{6}He decays of the linear-chains in ^{16}C

TL;DR

This paper investigates the linear-chain states of carbon-16 using antisymmetrized molecular dynamics, revealing their configurations, decay modes, and rotational band structures with specific decay channels and large moments of inertia.

Contribution

It provides a detailed theoretical analysis of the configurations, decay modes, and rotational properties of linear-chain states in $^{16}$C, including positive and negative parity states with novel decay channel insights.

Findings

Positive-parity states decay to $^{12}$Be via alpha emission.

Negative-parity states exhibit two types of linear-chains with distinct configurations.

Both types of states form rotational bands with large moments of inertia.

Abstract

The linear-chain states of $^{16}$C and their decay modes are theoretically investigated by using the antisymmetrized molecular dynamics. It is found that the positive-parity linear-chain states have the $(3/2^-_\pi)^2(1/2^-_\sigma)^2$ configuration and primary decay to the $^{12}$Be($2^+_1$) as well as to the $^{12}$Be(g.s.) by the $\alpha$ particle emission. Moreover, we show that they also decay to the $^6{\rm He}+{}^{10}{\rm Be}$ channel. In the negative-parity states, it is found that two types of the linear-chains exist. One has the valence neutrons occupying the molecular-orbits $(3/2^-_\pi)^2(1/2^-_\sigma)(3/2^+_\pi)$, while the other's configuration cannot be explained in terms of the molecular orbits because of the strong parity mixing. Both configurations constitute the rotational bands with large moment of inertia and intra-bands $E2$ transitions. Their $\alpha$ and ${}^{6}{\rm He}$ reduced widths are sufficiently large to be distinguished from other non-cluster states although they are smaller than those of the positive-parity linear-chain.