Neutron-unbound states in (25,26)F
Neutron-unbound states in (25)F and (26)F were populated via the reactions (9)Be((26)Ne,(24)F + n) and (9)Be((26)Ne, (25)F + n), respectively. A resonance close to the neutron separation energy in (25)F was identified with a decay energy of 28 +/- 4 keV. This resonance corresponds to an excited state in (25)F at 4249 +/- 116 keV assuming it decays to the ground state of (24)F. Guided by shell-model calculations, a spin and parity of 1/2(-) can be assigned to this state. In the spectrum of (26)F, which was produced in a nucleon-exchange reaction, there are indications for an excited state with a decay energy of similar to 270 keV.
Published in: Physical Review C, Volume 84, Issue 3, September 6, 2011. The final published version is available at: http://dx.doi.org/10.1103/PhysRevC.84.037302