Particle- γ coincidence spectroscopy of the N = 90 nucleus 154Gd by (p, tγ)
- Author(s): Allmond, JM
- Beausang, CW
- Ross, TJ
- Humby, P
- Basunia, MS
- Bernstein, LA
- Bleuel, DL
- Brooks, W
- Brown, N
- Burke, JT
- Darakchieva, BK
- Dudziak, KR
- Evans, KE
- Fallon, P
- Jeppesen, HB
- LeBlanc, JD
- Lesher, SR
- McMahan, MA
- Meyer, DA
- Phair, L
- Rasmussen, JO
- Scielzo, ND
- Stroberg, SR
- Wiedeking, M
- et al.
Published Web Location
https://doi.org/10.1140/epja/i2017-12253-2Abstract
© 2017, SIF, Springer-Verlag Berlin Heidelberg. A segmented Si-telescope and HPGe array, STARS-LIBERACE, was used to study the 156Gd(p, tγ)154Gd direct reaction by particle- γ coincidence spectroscopy. New cross sections with a 25MeV proton beam are reported and compared to previous (p,t) and (t,p) studies. Furthermore, additional evidence for coexisting Kπ=01+,21+ and 02+, 22+ configurations at N = 90 is presented. Direct and indirect population patterns of the low-lying states are also explored. Review of the new and existing evidence favors an interpretation based on a configuration-dependent pairing interaction. The weakening of monopole pairing strength and an increase in quadrupole pairing strength could bring 2p-2h 0 + states below 2 Δ. This may account for a large number of the low-lying 0 + states observed in two-nucleon transfer reactions. A hypothesis for the origin of the 02+ and 03+ states is provided.