Executive Summary : | The research project aims to study the structure of nuclei in the lighter mass region using low-energy Coulomb-excitation (CE) measurements. This technique allows for the direct determination of electric quadrupole matrix elements of nuclear states, which are proportional to the spectroscopic quadrupole moment, Qs(2+). Nuclear shape plays a crucial role in understanding the underlying shell structure. Nuclei with both proton and neutron numbers close to magic numbers are generally spherical in their ground states due to the insufficient number of valance particles. However, moving away from the closed shell causes deformation due to the availability of a large number of valence particles. The doubly magic nucleus ⁴⁰Ca (N = Z = 20) is one of the best examples for observing multiple nuclear shape-coexistence and can be established through low-energy CE measurements. The systematic observation of silicon isotopes 28-42Si (Z = 14) shows dramatic changes in deformations with increasing neutron number, indicating the collapse of N=28 magic shell closure in ⁴²Si. The project aims to determine the nuclear matrix elements, sign and magnitude of spectroscopic quadrupole moments, QS(2+) of low-lying states in ³⁰Si and ⁴⁰Ca through safe Coulomb-excitation reorientation measurements employing particle-γ coincidence technique. A precise determination of QS(2+) plays a crucial role in elucidating effective nuclear interactions on the possible N=16 neutron sub shell gape or large deformation in ³⁰Si and quintuple shape-coexistence in ⁴⁰Ca. |