Investigation of the near-threshold cluster resonance in $^{14}\rm{C}$

TL;DR

This paper reports the experimental identification of excited states in $^{14}$C, including a new state at 18.3 MeV, revealing insights into near-threshold cluster resonances and molecular configurations.

Contribution

It presents the first observation of a new excited state in $^{14}$C at 18.3 MeV and confirms a state at 14.1 MeV linked to a molecular rotational band.

Findings

Discovery of a new excited state at 18.3 MeV in $^{14}$C.

Identification of a 14.1 MeV state consistent with a molecular rotational band.

Use of a specialized telescope system to detect near-threshold resonances.

Abstract

An experiment for $p(^{14}\rm{C}$,$^{14}\rm{C}^{*}\rightarrow^{10}\rm{Be}+\alpha)\mathit{p}$ inelastic excitation and decay was performed in inverse kinematics at a beam energy of 25.3 MeV/u. A series of $^{14}\rm{C}$ excited states, including a new one at 18.3(1) MeV, were observed which decay to various states of the final nucleus of $^{10}\rm{Be}$. A specially designed telescope-system, installed around the zero degree, played an essential role in detecting the resonant states near the $\alpha$-separation threshold. A state at 14.1(1) MeV is clearly identified, being consistent with the predicted band-head of the molecular rotational band characterized by the $\pi$-bond linear-chain-configuration. Further clarification of the properties of this exotic state is suggested by using appropriate reaction tools.