Excitation functions of fusion reactions and neutron transfer in the interaction of 6He with 197Au and 206Pb

Abstract

206 Pb( 6 He,2n) 210 Po, as well as for the transfer reactions on a 197 Au target with the formation of the 196 Au and 198 Au isotopes, with a beam dose about a factor of 10 higher and, in addition, at energies considerably lower than the Coulomb barrier of the reactions.

2n-Evaporation Channel In The4,6He+208,206Pb Fusion Reactions

“…The experiment [4,5] performed in FLNR (JINR), Dubna in 2006 at the accelerator complex for radioactive beams DRIBs [12] confirmed the results on the enhancement of fusion close to the Coulomb barrier, when halo nuclei are involved. In this experiment the cross sections for the formation of compound nuclei as a function of energy were measured.…”

“…In this experimental method (the additional detail were given in Refs. [4,5]), according to the size of the targets along the focal plane (20 mm) and the dispersion of the magnetic spectrometer MSP-144 (~40 keV/mm), the energy resolution of the beam amounted to ±400 keV. In this case the intensity of the beam was 2×10 7 pps.…”

“…In particular, nuclei with large neutron excess are known to manifest a phenomenon known as neutron halo or skin. At low energies around the interaction barrier, nuclear structure manifests itself in complete fusion reactions with the formation of a compound nucleus or in the transfer of a few nucleons from the projectile to the target nucleus [3][4][5].…”

“…Recently a series of experiments have been performed with the aim to study the fusion-fission process using 6 He beams with close-to-barrier energies [3][4][5][9][10][11]. However, the obtained data were rather controversial and showed that higher statistical confidence is necessary as well as more informative experiments giving possibilities of distinguishing different exit reaction channels.…”

“…Excitation functions of the reaction products were measured for the reactions induced by 4,6 He projectiles on 208,206 Pb targets, leading to the same compound nucleus. The excitation functions for the 2n evaporation channels were obtained at energies below the sub-Coulomb barrier region.…”