# Nuclear track emulsion in search for the Hoyle-state in dissociation of relativistic ${}^{12}$C nuclei

## TL;DR

This study uses nuclear track emulsion to identify Hoyle state decays in relativistic ${}^{12}$C dissociation, providing insights into nuclear structure and decay processes with high angular measurement precision.

## Contribution

It demonstrates a method to detect Hoyle state contributions in ${}^{12}$C dissociation using nuclear track emulsion with precise angular measurements.

## Key findings

- Estimated 10-15% contribution of Hoyle state to ${}^{12}$C dissociation.
- Reconstructed Hoyle state decays via alpha particle emission angles.
- Identified ${}^{8}$Be nucleus in decay processes.

## Abstract

Production of ensembles of $\alpha$-particle triples associated with the Hoyle state (the second excited state of the ${}^{12}$C nucleus) in peripheral dissociation of relativistic ${}^{12}$C nuclei is studied. Stacks of nuclear track emulsion pellicles exposed to ${}^{12}$C with an energy from hundreds MeV to a few GeV per nucleon serve as the material for studies. The Hoyle state decays are reconstructed via measurement of emission angles of $\alpha$ particles with the precision sufficient for identification of the unstable ${}^{8}$Be nucleus. The estimate of the contribution of Hoyle's state to the ${}^{12}$C $\to$ 3$\alpha$ dissociation is 10-15\%.