α-particle production in the scattering of 6He by Pb-208 at energies around the Coulomb barrier

16 pages, 5 figures, 2 tables.-- PACS nrs.: 24.10.Eq; 24.50.+g; 25.70.Mn; 25.70.Hi.-- Printed version published Aug 2007.-- ArXiv pre-print available at: http://arxiv.org/abs/0705.1678
New experimental data from the scattering of 6He + Pb-208 at energies around and below the Coulomb barrier are presented. The yield of breakup products coming from projectile fragmentation is dominated by a strong group of a particles. The energy and angular distribution of this group have been analyzed and compared with theoretical calculations. This analysis indicates that the a particles emitted at backward angles in this reaction are mainly due to two-neutron transfer to weakly bound states of the final nucleus.
This work has been supported by the Spanish MCyT projects FPA2005-04460, FPA2005-02379, FPA-2000-1592-C03-02, FPA2003-05958, and FPA2002-04181-C04-02/03, by the European Community-Access to Research Infrastructure action of the Improving Human PotentialProgram, contract number HPRI-CT-1999-00110 and the Belgian program P5/07 on interuniversity attraction poles of the Belgian-state Federal Services for Scientific, Technical and Cultural Affairs. We are grateful to J. Kolata for useful discussions. A.M.M. acknowledges financial support by the Junta de Andalucía. D.E. acknowledges financial support by the MEC.