- Tripathi, V
- Lubna, RS
- Abromeit, B
- Crawford, HL
- Liddick, SN
- Utsuno, Y
- Bender, PC
- Crider, BP
- Dungan, R
- Fallon, P
- Kravvaris, K
- Larson, N
- Macchiavelli, AO
- Otsuka, T
- Prokop, CJ
- Richard, AL
- Shimizu, N
- Tabor, SL
- Volya, A
- Yoshida, S
- et al.
© 2017 American Physical Society. Low-lying excited states in P38,40 have been identified in the β decay of Tz=+5,+6, Si38,40. Based on the allowed nature of the Gamow-Teller (GT) decay observed, these states are assigned spin and parity of 1+ and are core-excited 1p1h intruder states with a parity opposite to the ground state. The occurrence of intruder states at low energies highlights the importance of pairing and quadrupole correlation energies in lowering the intruder states despite the N=20 shell gap. Configuration interaction shell model calculations with the state-of-art SDPF-MU effective interaction were performed to understand the structure of these 1p1h states in the even-A phosphorus isotopes. States in P40 with N=25 were found to have very complex configurations involving all the fp orbitals leading to deformed states as seen in neutron-rich nuclei with N≈28. The calculated GT matrix elements for the β decay highlight the dominance of the decay of the core neutrons rather than the valence neutrons.