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The excited states of 26Al have been produced and studied using 27Al(d,t) reaction with 25 MeV deuteron as projectile. Optical model potential parameters were extracted from the measured elastic scattering angular distribution. Zero range distorted wave Born approximation analysis for the ground and 0.223 MeV states of 26Al have been done. The spectroscopic factors calculated for these states are found to be in good agreement with the previously reported values.

Fragment emission mechanisms have been studied in 12C on 12C and 13C on 12C reactions at same excitation energy. The inclusive energy distributions of the complex fragments (3≤ Z ≤ 5) emitted from the composite system have been measured in the angular range 14° to 36°. The present experiments have been performed with the motivation to study the isotopic dependence of fragment yields in these two reactions. From the preliminary analysis, it has been observed that fragments are emitted from a completely equilibrated and long lived composite system for both 12C + 12C and 13C + 12C reactions. It has also been observed that the emission of neutron-rich fragments are more in 13C + 12C compared to 12C + 12C reaction.

Neutron evaporation spectra alongwith γ-multiplicity has been measured from the 185Re* compound nucleus at the excitation energies ~27 and 37 MeV. Statistical model analysis of the experimental data has been carried out to extract the value of the inverse level density parameter k at different angular momentum regions (J) corresponding to different γ-multiplicity. It is observed that, for the present system the value of k remains almost constant for different J. The present results on the angular momentum dependence of the nuclear level density (NLD) parameter ã (=A/k), for nuclei with A ~180 is quite different from our earlier measurements in case of light and medium mass systems. The present analysis provides useful information to understand the angular momentum dependence of NLD at different nuclear mass regions.

An excited state of 12C having excitation energy (Ex) 9.65 ± 0.02 MeV and width (FWHM) 607 ± 55 keV, which decays to three α particles via Hoyle state (Ex = 7.65 MeV), has been directly identified in the exclusive inelastic scattering of 60 MeV 4He on 12C, measured in coincidence with the recoiling 12C Hoyle state (decaying mostly as 12C* → 8Begs → α → α + α + α) by event-by-event kinematic reconstruction of the completely detected (4α) events. This state is likely to be a candidate for 22+ first excited of Hoyle state.

The quantitative contributions of various direct three alpha decay mechanisms in the decay of the famous Hoyle state, the 02+ resonant excited state of 12C at excitation energy of 7.65 MeV, has been estimated using 60 MeV α inelastic scattering on 12C target in complete kinematical measurement. Simultaneous optimisation of three different distributions (the relative energy of 8Be like pairs, the root mean square energy deviation and the radial projection of symmetric Dalitz plot) derived from the experimental data with those generated from the Monte Carlo simulated event sets, have been done to arrive at a consistent estimation of the contributions of various direct decay modes.

The reaction 27Al(d,t) at 25 MeV was utilized to study the excited states of 26Al. The angular distributions of the observed excited states of 26Al were analyzed with zero range distorted wave Born approximation as well as by incorporating finite range correction parameters to extract spectroscopic factors. The two sets of extracted spectroscopic factors were compared with each other to see the effect of using finite range correction in the transfer form factor.

The high-spin states in 197Tl were studied by populating them using the 197Au(α, 4n)197 Tl reaction at 48 MeV of beam energy. γ−γ coincidence data were taken using a combination of clover, LEPS (low energy photon spectrometer) and single crystal HPGe detectors. The polarization and DCO measurements were performed for definite spin and parity assignment of the excited states. The πi13/2 intruder state has been identified for the first time in this nucleus. The total Routhian surface calculations have been performed to study the shape and deformation of 197Tl for different configurations.

Fission fragment mass distribution has been measured in two reactions to populate compound nucleus 246Bk. Both the target nuclei were deformed. However, entrance channel mass asymmetry of the two systems was on the either side of the Businaro Gallone mass asymmetry parameter. Near the Coulomb barrier, at similar excitation energies, the width of the fission fragment mass distribution was found to be significantly different for the 14N+232Th reaction compared to the 11B+235U reaction. The entrance channel mass asymmetry was found to play a significant role in deciding the fusion process.