Cluster radioactivity leading to doubly magic 100Sn and 132Sn daughters

Decay of neutron-deficient Gd128-137 parents emitting He-4 to S-32 clusters are studied within the Coulomb and proximity potential model. The predicted half-lives are compared with other models and most of the values are well within the present experimental limit for measurements (T-1/2 < 10(30) s). The lowest T-1/2 value for Si-28 emission from Gd-128 indicates the role of doubly magic Sn-100 daughter in cluster decay process. It is also found that neutron excess in the parent nuclei slows down the cluster decay process. Geiger-Nuttal plots for all clusters are found to be linear with different slopes and intercepts. The a-decay half-lives of Gd148-152 parents are computed and are in agreement with experimental data. The role of doubly magic Sn-132 daughter in cluster decay process is also examined for various neutron-rich Ba, Ce, Nd, Sm and Gd parents emitting clusters ranging from 4He to Si-32. Alpha-like structures are most probable in the decays leading to Sn-100, while non-a-like structures are probable in the decays leading to Sn-132. The neutron proton asymmetry in parent and daughter nuclei is responsible for the reduced decay rate in the decay leading to Sn-132.