https://doi.org/10.1140/epja/i2016-16005-6
Regular Article - Theoretical Physics
First-forbidden
-decay rates, energy rates of
-delayed neutrons and probability of
-delayed neutron emissions for neutron-rich nickel isotopes
1
Faculty of Engineering Sciences, GIK Institute of Engineering Sciences and Technology, Swabi, Topi 23640, Khyber Pakhtunkhwa, Pakistan
2
Department of Physics, Karabük University, 78050, Karabük, Turkey
* e-mail: jameel@giki.edu.pk
Received:
11
July
2015
Accepted:
10
December
2015
Published online:
14
January
2016
First-forbidden (FF) transitions can play an important role in decreasing the calculated half-lives specially in environments where allowed Gamow-Teller (GT) transitions are unfavored. Of special mention is the case of neutron-rich nuclei where, due to phase-space amplification, FF transitions are much favored. We calculate the allowed GT transitions in various pn-QRPA models for even-even neutron-rich isotopes of nickel. Here we also study the effect of deformation on the calculated GT strengths. The FF transitions for even-even neutron-rich isotopes of nickel are calculated assuming the nuclei to be spherical. Later we take into account deformation of nuclei and calculate GT + unique FF transitions, stellar -decay rates, energy rate of
-delayed neutrons and probability of
-delayed neutron emissions. The calculated half-lives are in excellent agreement with measured ones and might contribute in speeding-up of the r-matter flow.
© SIF, Springer-Verlag Berlin Heidelberg, 2016