Role of the Delta Resonance in the Population of a Four-Nucleon State in the 56Fe to 54Fe Reaction at Relativistic Energies

Podolyak, Zs, Harkness-Brennan, LJ and Judson, DS (2016) Role of the Delta Resonance in the Population of a Four-Nucleon State in the 56Fe to 54Fe Reaction at Relativistic Energies. Physical Review Letters, 117 (22). 222302-.

Text 54fe_isomer_resubmitted_14sept2016.pdf - Author Accepted Manuscript Download (894kB)

Abstract

The 54Fe nucleus was populated from a 56Fe beam impinging on a Be target with an energy of E/A=500MeV. The internal decay via γ-ray emission of the 10+ metastable state was observed. As the structure of this isomeric state has to involve at least four unpaired nucleons, it cannot be populated in a simple two-neutron removal reaction from the 56Fe ground state. The isomeric state was produced in the low-momentum (-energy) tail of the parallel momentum (energy) distribution of 54Fe, suggesting that it was populated via the decay of the Δ0 resonance into a proton. This process allows the population of four-nucleon states, such as the observed isomer. Therefore, it is concluded that the observation of this 10+ metastable state in 54Fe is a consequence of the quark structure of the nucleons.

Item Type:	Article
Uncontrolled Keywords:	isomer decays, nuclear reactions
Depositing User:	Symplectic Admin
Date Deposited:	29 Nov 2016 14:53
Last Modified:	19 Jan 2023 07:24
DOI:	10.1103/PhysRevLett.117.222302
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3004696