The effect of positive Qxn-value
neutron transfer
on sub-barrier fusion reaction, H. Jia, China
Institute of
Atomic Energy, China − Positive Qxn-value neutron transfer
effect on the
fusion reaction near the Coulomb barrier has been proposed for
almost three
decades theoretically. The
role is still
far from good understanding due to the difficult theoretical
description and
inconsistent experimental results. We
decided
to measure the fusion excitation functions of 32S+90,94,96Zr,
18O+74Ge, and 16O+76Ge
at
near-barrier energy range by using an electrostatic deflector
setup at HI-13
tandem accelerator of CIAE, in which some with positive Qxn-value
neutron
transfer and others with negative ones but with similar collective
properties
for reference. The
reaction products
were separated by electrostatic fields, and then identified by the
TOF-E
method. For these
measured systems,
large fusion enhancement emerges for 32S+94,96Zr
compared
with 32S+90Zr, but no enhancement exists
for 18O+74Ge
compared with 16O+76Ge although of the
positive Q2n
transfer channel for the first system.