Study of the break-up channel in 11Li+208Pb collisions at energies around the Coulomb barrier

International Symposium on Entrance Channel Effect on the Reaction Mechanism in Heavy Ion Collisions

Fernández-García, J.P.^1,2,3 ; Cubero, M.^4,5,6 ; Rodríguez-Gallardo, M.^1 ; Acosta, L.^3,7 ; Alcorta, M.^2 ; Alvarez, M.A.G.^1,2 ; Borge, M.J.G.^4 ; Buchmann, L.^8 ; Diget, C.A.^9 ; Falou, H.A.^10 ; Fulton, B.R.^9 ; Fynbo, H.O.U.^11 ; Galaviz, D.^12 ; Gómez-Camacho, J.^1,2 ; Kanungo, R.^10 ; Lay, J.A.^1,13 ; Madurga, M.^4 ; Martel, I.^7 ; Moro, A.M.^1 ; Mukha, I.^14 ; Nilsson, T.^15 ; Sánchez-Benítez, A.M.^7,12 ; Shotter, A.^16 ; Tengblad, O.^4 ; Walden, P.^8

Departamento de FAMN, Universidad de Sevilla, Apartado 1065, E-41080 Sevilla, Spain^1

Centro Nacional de Aceleradores, Universidad de Sevilla/Junta de Andalucía/CSIC, E-41092 Sevilla, Spain^2

Istituto Nazionali di Fisica Nucleare-Laboratori Nazionali Del Sud (INFN-LNS), I-95123 Catania, Italy^3

Instituto de Estructura de la Materia-CSIC, E-28006 Madrid, Spain^4

Centro de Investigación en Ciencias Atómicas, Nucleares y Moleculares (CICANUM), CR-2060 San Jose, Costa Rica^5

Instituto de Fisica, Universidade Federal Fluminense, Av. Litoranea s/n, Niteroi, R.J., Brazil^6

Departamento de Física Aplicada, Universidad de Huelva, E-21071 Huelva, Spain^7

TRIUMF, Vancouver BC V-6T2A3, Canada^8

Departament of Physics, University of York, YO1O-5DD Heslington, York, United Kingdom

(10) Department of Astronomy and Physics, Saint Marys University, Halifax B3H3C3, Canada

(11) Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus, Denmark

(12) Centro de Fisica Nuclear da Universidade de Lisboa (CFNUL), 1649-003 Lisbon, Portugal

(13) Dipartimento di Fisica e Astronomia galileo Galilei, Universita di Padova e INFN, Sezione di Padova, 8 via Marzolo, I-35131 Padova, Italy

(14) GSI Helmholtzzentrum Fr Schwerionenforschung GmbH, Planckstr 1, D-64291 Darmstadt, Germany

(15) Fundamental Physics, Chalmers University of Technology, S-41296 Gteborg, Sweden

(16) School of Physics and Astronomy, University of Edinburgh, EH9 3JZ Edinburgh, United Kingdom^9

关键词: Coulomb barrier;    Coupled channels;    Dipole resonances;    First order;    Low-excitation energy;    Semi-classical calculations;    Vancouver , Canada;    Weak binding;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/515/1/012004/pdf
DOI  :  10.1088/1742-6596/515/1/012004

来源: IOP

【 摘 要 】

We present a study of11Li+208Pb collisions at energies around the Coulomb barrier (Elab 24.3 and 29.8 MeV), measured at the post-accelerated beam facility, ISAC II, at TRIUMF (Vancouver, Canada). A remarkably large yield of9Li has been observed, a result that is attributed to the weak binding of the11Li nucleus. The angular distribution of this9Li yield, relative to the elastic one, has been analysed in terms of first-order semiclassical calculations as well as four-body and three-body Continuum-Discretized Coupled-Channels (CDCC) calculations, based on a three-body and di-neutron model of the11Li nucleus, respectively. The calculations reproduce well the trend of the data and support the existence of a large concentration of B(E1) strength at very low excitation energies. The connection of this large B(E1) with a possible low-lying dipole resonance is discussed.