Production cross section of At radionuclides from ${}^7$Li+${}^{\text{nat}}$Pb and ${}^9$Be+${}^{\text{nat}}$Tl reactions

Earlier we reported theoretical studies on the probable production of astatine radionuclides from ${}^{6,7}$Li and ${}^9$Be-induced reactions on natural lead and thalliun targets, respectively. For the first time, in this report, production of astatine radionuclides has been investigated experimentally with two heavy ion induced reactions: ${}^9$Be+${}^{\text{nat}}$Tl and ${}^7$Li+${}^{\text{nat}}$Pb. Formation cross sections of the evaporation residues, ${}^{207,208,209,210}$At, produced in (HI, xn) channel, have been measured by the stacked-foil technique followed by the off-line $\gamma$-spectrometry at the low incident energies ($<$50 MeV). Measured excitation functions have been explained in terms of compound nuclear reaction mechanism using Weisskopf-Ewing and Hauser-Feshbach model. Absolute cross section values are lower than the respective theoretical predictions.