Frontiers in Gamma Ray Spectroscopy FIG18

Investigation of fragment capture reaction mechanism involving weakly bound 7Li

13 Mar 2018, 14:30

15m

AG66 (TIFR, Mumbai)

Oral

Speaker

Mr Sanat Pandit (Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai - 400085, India)

Description

The dynamics of the reactions involving weakly bound nuclei is a topic of current interest [1-3]. The low breakup threshold of such nuclei leads to the breakup as well as fragment-capture reaction processes and consequently affect the reaction dynamics. Here, the fragment capture reaction mechanisms have been studied for 7Li + 93Nb system. Exclusive particle-γ coincidence measurements were performed at energies near the Coulomb barrier to identify the various fragment capture processes uniquely [4]. The prompt γ-ray measurements were performed using Indian National Gamma Array (INGA). Three Si surface barrier telescopes were used for the detection of charged particles. The absolute cross-sections of t-capture, α-capture, 2n-stripping and complete fusion reactions were measured using the in-beam and off-beam γ-ray counting methods. The measured cross-section of t-capture and α-capture could be explained by dynamical trajectory model calculations PLATYPUS [5], using the model parameters that reproduced the breakup and fusion data for the same system. The cross-sections for p- d- t-stripping, predicted from the Distorted wave Born approximation calculations were found to be negligible. These two results indicate the dominance of the two-step process, breakup followed by fusion, over the one-step process of cluster-stripping process [6]. [1] L. F. Canto et al., Phys. Rep. 596, 1 (2015). [2] A. Shrivastava et al., Phys. Lett. B 718, 931 (2013). [3] N. Keeley et al., Prog. Part. Nucl. Phys. 63, 396 (2009). [4] S. K. Pandit et al., Phys. Rev. C 96, 044616 (2017). [5] A. Diaz Torres et al., Phys. Rev. Lett. 98, 152701 (2007). [6] S. K. Pandit et al., to be published.