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Thin isotopically enriched 156 , 158 Gd target foils of thickness between ≈ 100– 150 μ g /cm2 have been fabricated. The target foils were prepared on carbon backing to provide extra support using the physical vapor deposition (PVD) technique. The fabricated target foils have been used to study the dynamics of heavy-ion induced fusion reactions using the Heavy Ion Reaction Analyser (HIRA) facility at IUAC New-Delhi, India. Due to the high melting point, the e-gun method was adopted to deposition carbon and gadolinium. During fabrication, the challenges were (i) minimal isotopic material, (ii) selection of the parting agent, and (iii) the floating process for separating the gadolinium film from the glass slides. In view of this, the first several attempts have been made with natural gadolinium oxide material to optimize specific parameters. Finally, using only ≈ 38 mg isotopically enriched material for each isotope, eight 156Gd and twenty 158Gd targets were prepared successfully. The nobleness of this work is that the gadolinium material was in oxide form, which provides extra stability to the fabricated targets even in the atmospheric environment. Further, various characterization techniques such as Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), X-ray Diffractometry (XRD), and Rutherford Back-scattering Spectroscopy (RBS), have been explored to investigate surface morphology, elemental purity, chemical composition, and thickness of the target foils. The characterizations and analysis of experimental data manifested that no such impurities were present in the fabricated target foils. Essentially, it has been observed that the fabricated thin 156 , 158 Gd target foils survived against the heavy-ion ( 28 , 30 Si) irradiation throughout the online fusion experiment. • Fabrication of thin isotopically enriched 156,158Gd foils. • 156,158Gd target preparation for nuclear reaction studies. • Physical vapor deposition of gadolinium oxides. • Characterization of fabricated 156,158Gd foils. [ABSTRACT FROM AUTHOR]

Measurements on multinucleon transfer reactions for 28Si+90,94Zr systems were performed at sub- and near-barrier energies. The fact that 90Zr has a closed neutron shell (N = 50) and 94Zr has four neutrons outside the closed shell, allows us to investigate the effects of shell closure and pairing correlation on multinucleon transfer mechanism. The experiment was performed with pulsed 28Si beam using the Heavy Ion Reaction Analyzer (HIRA) at Inter University Accelerator Centre (IUAC), New Delhi. Based on the Q-value considerations, it turned out that pickup channels were neutron transfer whereas stripping channels were proton transfer. For the 28Si+90Zr system, the values of the slope parameter for two-neutron pickup turned out to be less than that for one-neutron pickup. The values of the slope parameter were almost the same for two-, three-, and four-neutron pickup channels in the case of the 28Si+94Zr system. The transfer probabilities in the case of the 28Si+94Zr system were much larger than those for the 28Si+90Zr system, further supporting the fact that there is a correlation between the transfer channels and sub-barrier fusion cross-section enhancement. An odd-even staggering was observed in the extracted transfer probabilities at the barrier radius implying the role of pairing correlation in transfer reactions. [ABSTRACT FROM AUTHOR]