Speaker
Thomas Neff
(GSI Darmstadt)
Description
We calculate the radiative capture cross sections for the 3He(a,g)7Be
and the 3H(a,g)7Li reactions [1] in the fully microscopic Fermionic
Molecular Dynamics approach [2] using a realistic effective interaction
obtained in the Unitary Correlation Operator Method [3]. At large
distances bound and scattering states are described by antisymmetrized
products of 4He and 3He/3H ground states. At short distances the
many-body Hilbert space is extended with additional many-body wave
functions obtained by variation after parity and angular momentum
projection. These additional configurations are needed to represent
polarized clusters and shell-model like configurations. Properties of
the bound states like binding energies, charge radii and quadrupole
moments are described well, as are the scattering phase shifts. The
calculated S-factor for the 3He(a,g)7Be reaction agrees very well with
recent experimental data both in absolute normalization and energy
dependence. In case of the 3H(a,g)7Li reaction the calculated S-factor
is larger than the experimental data by about 15%. We analyze the
bound and scattering wave functions using overlap functions and find
that a significant part of the cross section is important to treat the
wave functions properly at short distances.
[1] T. Neff, Phys. Rev. Lett. 106, 042502 (2011)
[2] T. Neff, H. Feldmeier, Eur. Phys. J Special Topics 156, 69 (2008)
[3] R. Roth, T. Neff, H. Feldmeier, Prog. Part. Nucl. Phys. 65, 50 (2010)
Primary author
Thomas Neff
(GSI Darmstadt)
