TY  - JOUR
AU  - Podolyak, Z.
PY  - 2016
DA  - 2016//
TI  - Role of the Delta Resonance in the Population of a Four-Nucleon State in the Fe-56 -> Fe-54 Reaction at Relativistic Energies
T2  - Phys. Rev. Lett.
JO  - Physical Review Letters
SP  - 222302
EP  - 6pp
VL  - 117
IS  - 22
PB  - Amer Physical Soc
AB  - The Fe-54 nucleus was populated from a Fe-56 beam impinging on a Be target with an energy of E/A = 500 MeV. The internal decay via gamma-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 Fe-56 ground state. The isomeric state was produced in the low-momentum (-energy) tail of the parallel momentum (energy) distribution of Fe-54, suggesting that it was populated via the decay of the Delta(0) resonance into a proton. This process allows the population of fournucleon states, such as the observed isomer. Therefore, it is concluded that the observation of this 10(+) metastable state in Fe-54 is a consequence of the quark structure of the nucleons.
SN  - 0031-9007
UR  - https://doi.org/10.1103/PhysRevLett.117.222302
DO  - 10.1103/PhysRevLett.117.222302
LA  - English
N1  - WOS:000388630000009
ID  - Podolyak2016
ER  -