International Topical Meeting on Nuclear Research Applications and Utilization of Accelerators

4-8 May 2009, Vienna

Measurement of Cross-Sections in some Reactions in ¹⁶O + ¹⁸¹Ta System at Energies ~5 MeV/nucleon

R. Prasad¹, P.D. Singh¹, A. Yadav¹, P.P. Singh¹, Unnati¹, M.K. Sharma¹, B.P. Singh¹, R. Prasad¹, R. Kumar², K.S. Golda², and A.K. Sinha³

¹Department of Physics, Aligarh Muslim University, Aligarh, India
²Inter University Accelerator Centre, New Delhi, India
³UGC–DAE, CSR, Kolkata, India

Corresponding Author: rpm166@rediffmail.com

In view of the recent advances in Accelerator Driven Energy Systems (ADES), there is a great need of precise data on reaction cross-sections induced not only by light but also by heavy ions (HIs). The HI-induced reaction data is also needed for environmental and medical applications. Further, the reaction mechanism for HI interaction at energies near and just above the Coulomb barrier (CB) is not well understood. Both complete and incomplete fusion mechanism are likely to compete at these energies. With above view in sight, the excitation functions (EFs) for several reactions ¹⁸¹Ta(¹⁶O, 3n)¹⁹⁴Tl, ¹⁸¹Ta(¹⁶O, 4n)¹⁹³Tl, ¹⁸¹Ta(¹⁶O, 5n)¹⁹²Tl, ¹⁸¹Ta(¹⁶O, p3n)^193m,gHf, ¹⁸¹Ta(¹⁶O, p4n)¹⁹²Hf, ¹⁸¹Ta(¹⁶O, p5n)^191m,gHf, ¹⁸¹Ta(¹⁶O, 2p2n)^193mAu, ¹⁸¹Ta(¹⁶O, αn)¹⁹²Au, ¹⁸¹Ta(¹⁶O, α2n)¹⁹¹Au and ¹⁸¹Ta(¹⁶O, α3n)¹⁹⁰Au produced both by complete and incomplete fusion in ¹⁶O +¹⁸¹Ta system at energies varying from the Coulomb barrier to ~5 MeV/nucleon has been measured. The experimental data has been analysed within the frame work of complete and incomplete fusion (ICF) formalisms. The analysis of the data indicates that the experimentally measured EFs for reaction channels produced by the emission of protons or neutrons and/or by both agree well with the theoretical predictions of the code based on statistical model formalisms. However, for α emission channels, the enhancement of the experimentally measured EFs has been observed in comparison with the theoretical predictions of the model calculations based on CN theory, indicating the significant contribution of incomplete fusion channels. Furthermore, in the present work energy dependence of ICF components has also been deduced. Details of experiments and analysis will be presented.

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