By using 14 different versions and parametrizations of a proximity potential and two new versions of the potential proposed in this paper, we perform a comparative study of fusion barriers by studying 26 symmetric reactions. The mass asymmetry $\eta_{ A}$ = $(\frac{ A_{ 2}-A_{ 1}}{ A_{ 2}+A_{ 1}}),$ however, is very large. Our detailed investigation reveals that most of the proximity potentials reproduce experimental data within $\pm$8% on the average. A comparison of fusion cross sections indicates that Bass 80, AW 95, and Denisov DP potentials have a better edge than other potentials. We also propose new versions of the proximity potential as well as Denisov parametrized potential. These new versions improve the agreement with the data.
Categories: nucl-th