Cold valleys in the radioactive decay of  248-254Cf  isotopes

 

R K BIJU1, SABINA SAHADEVAN1, K P SANTHOSH1,*  and ANTONY JOSEPH2

1P.G. Department of Physics and Research Centre, Payyanur College,

Payyanur 670 327, India

2Department of Physics, Calicut University, Calicut 670 635, India

*Corresponding author. E-mail: kpsanthosh@eth.net; kps@calicutcity.com

 

Abstract. Based on the concept of cold valley in cold fission and

fusion, we have investigated the cluster decay process in

$^{248-254}$Cf isotopes. In addition to alpha particle minima, other

deep minima occur for S, Ar and Ca clusters. It is found that

inclusion of proximity potential does not change the position of

minima but minima become deeper. Taking Coulomb and proximity

potential as interacting barrier for post-scission region, we

computed half-lives and other characteristics for various clusters

from these parents. Our study reveals that these parents are stable

against light clusters and unstable against heavy clusters. Computed

half-lives for alpha decay agree with experimental values within two

orders of magnitude. The most probable clusters from these parents

are predicted to be $^{46}$Ar, $^{48,50}$Ca which indicate the role

of doubly or near doubly magic clusters in cluster radioactivity. Odd

A clusters are found to be favorable for emission from odd A parents.

Cluster decay model is extended to symmetric region and it is found

that symmetric fission is also probable which stresses the role of

doubly or near doubly magic $^{132}$Sn nuclei. Geiger--Nuttal plots

were studied for various clusters and are found to be linear with

varying slopes and intercepts.

 

Keywords. Cluster decay; alpha decay.

 

PACS Nos 23.70.+j; 25.85.Ca; 27.90.+b