In-beam gamma-ray spectroscopy, carried out at the Saha Institute of Nuclear Physics in the recent past, using heavy-ion projectiles from the pelletron accelerator centres in the country and multi-detector arrays have yielded significant data on the structure of a large number of nuclei spanning different mass regions. The experiments included the study of two-fold $\gamma\gamma$-coincidence events for establishing decay schemes, directional correlation of oriented nuclei (DCO) for help in spin assignments and Doppler shift attenuation for lifetime information. The studies have led to the observation of rotational sequences of states in nuclei near closed shell in the mass $A = 110$ region, vibrational spectra in nuclei with $A\sim 60$, interplay between single-particle and collective modes of excitation in the doubly-odd bromine isotopes, decoupled bands with large quadrupole deformation in ⁷⁷Br, shape transition with rotational frequency within a band in ¹³⁸Pm and octupole collectivity in ¹⁵³Eu. Particle-rotor-model and cranked-shell-model calculations have been carried out to provide an understanding of the underlying nuclear structure

The effect of inelastic excitation of exotic light projectiles (proton-as well as neutron-rich)¹⁷F and¹¹Be on fusion with heavy target has been studied at near-barrier energies. The calculations have been performed in the coupled channels approach where, in addition to the normal coupling of the ground state of the projectile to the continuum, inelastic excitation of the projectile to the bound excited state and its coupling to the continuum have also been taken into consideration. The inclusion of these additional couplings has been found to have significant effect on the fusion excitation function of neutron-rich¹¹Be on²⁰⁸Pb whereas the effect has been observed to be nominal for the case of proton-rich¹⁷F on the same target. The pronounced effect of the channel coupling on the fusion process in the case of¹¹Be is attributed to its well-developed halo structure.

In the present work, the excited states of ¹¹³Sb were populated in the ¹⁰⁰Mo(²⁰Ne, $p6n$) reaction at a beam energy of 136 MeV. States only up to $59/2^−$ were observed in the $\Delta J = 2$ band. Mean lifetimes for the five states (from 4460 to 7998 keV) were measured for the first time using Doppler shift attenuation method. An upper limit of the lifetime (0.14 ps) was estimated for the 9061 keV, $47/2^−$ state. The $B(E2)$ values, derived from the present lifetime results, correspond to a large quadrupole deformation of $\beta_2 = 0.32$. The observed reduction in the experimental $B(E2)$ values for the 918.4 keV (spin $39/2^− \to 35/2^−$) and 985 keV (spin $43/2^− \to 39/2^−$) transitions may be interpreted as due to the proton alignement in the $g_{7/2}$ orbital. The dynamic moment of inertia was observed to be about half of the rigid body value at the highest observed frequency.