English

Hoyle band and $\alpha$ condensation in ${^{12}{\rm C}}$

Nuclear Theory 2015-08-12 v1 Nuclear Experiment

Abstract

The excited states in 12C{^{12}{\rm C}} are investigated by using an extended version of the so-called Tohsaki-Horiuchi- Schuck-R\"opke (THSR) wave function, where both the 3α3\alpha condensate and 8Be+α{^{8}{\rm Be}} + \alpha cluster asymptotic configurations are included. A new method is also used to resolve spurious continuum coupling with physical states. We focus on the structures of the "Hoyle band" states, 22+2_2^+, and 42+4_2^+ states, which are recently observed above the Hoyle state and of the 03+0_3^+ and 04+0_4^+ states, which are also quite recently identified in experiment. Their resonance parameters and decay properties are reasonably reproduced. All these states have gaslike configurations of the 3α3\alpha clusters with larger root mean square radii than that of the Hoyle state. The Hoyle band is not simply considered to be the 8Be(0+)+α{^{8}{\rm Be}}(0^+) +\alpha rotation as suggested by previous cluster model calculations, nor to be a rotation of a rigid-body triangle-shaped object composed of the 3α3\alpha particles. This is mainly due to the specificity of the Hoyle state, which has the 3α3\alpha condensate structure and gives a rise to the 03+0_3^+ state with a prominent 8Be(0+)+α{^{8}{\rm Be}}(0^+)+\alpha structure as a result of very strong monopole excitation from the Hoyle state.

Keywords

Cite

@article{arxiv.1408.5855,
  title  = {Hoyle band and $\alpha$ condensation in ${^{12}{\rm C}}$},
  author = {Y. Funaki},
  journal= {arXiv preprint arXiv:1408.5855},
  year   = {2015}
}

Comments

5 pages, 2 figures, submitted to PRL