https://doi.org/10.1140/epjp/i2016-16226-0
Regular Article
Shell-model study of 31S at excitations relevant to the thermonuclear 30P(p,
)31S reaction rate
1
Laboratoire de Physique Appliquée et Théorique, Université Larbi Tébessi, 12022, Tébessa, Algeria
2
IPHC, CNRS/IN2P3, Université de Strasbourg, F-67037, Strasbourg, Cedex2, France
* e-mail: m_bouhelal@yahoo.fr
Received:
29
May
2015
Revised:
2
June
2016
Accepted:
10
June
2016
Published online:
5
July
2016
Recent experimental data about the 30P(p,) reaction have been reported, where a list of confirmed 31S excited states within 500 keV of the 30P(p,
)31S threshold at
keV and their properties were studied. Definitive constraints on
are only given for two levels; the other ones are either tentative (five states) or undefined (six states). In order to confirm the proposed spin/parity assignments and to determine the unknown ones a comparison with shell-model calculations is crucial. We have performed a shell-model calculation using the
PSDPF interaction to calculate the excitation energy spectrum of mass 31 ( 31S - 31P up to 7000 keV. Between 6100 and 6700 keV, an excitation energy region of astrophysical interest, we obtain a set of negative-parity states that are good candidates for the observed ones. A complete spectrum of positive- and negative-parity states can now be proposed based also on a comparison with the 31P spectrum up to 7000 keV.
© Società Italiana di Fisica and Springer-Verlag Berlin Heidelberg, 2016