Extended optical model analyses of elastic scattering and fusion cross sections for 6, 7 Li + 208 Pb systems at near-Coulomb-barrier energies by using a folding potential W. Y. So, T. Udagawa (University of Texas at Austin) K. S. Kim (Hankuk Aviation Univ ersity) B. T. Kim, S.W.H (Sung Kyun Kwan Univers ity) International Nuclear Physics Conference June 6, 2007
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Extended optical model analyses of elastic scattering and fusion cross sections
Extended optical model analyses of elastic scattering and fusion cross sections for 6, 7 Li + 208 Pb systems at near-Coulomb-barrier energies by using a folding potential. International Nuclear Physics Conference June 6, 2007. - PowerPoint PPT Presentation
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Extended optical model analyses of elastic scattering and fusion cross sections
for 6, 7 Li + 208Pb systems at near-Coulomb-barrier energies
by using a folding potential
W. Y. So, T. Udagawa (University of Texas at Austin)K. S. Kim (Hankuk Aviation University)B. T. Kim, S.W.H (Sung Kyun Kwan University)
International Nuclear Physics ConferenceJune 6, 2007
Normalization of folding potential for elastic scattering
G. R. Satchler and W. G. Love, Phys. Lett. B76, 23 (1978).
7Li6Li
G. R. Satchler and W. G. Love, Phys. Rep. 55, 183 (1979).
Normalization of Double Folding Potential
Breakup threshold energies- 1.48 MeV for 6Li- 2.47 MeV for 7Li
Breakup effect in elastic scattering
Coupled Discretized Continuum Channel (CDCC) By including breakup channel (6Li + d) and using folding potential, it was shown1. Normalization of folding potential is no longer needed.2. Breakup coupling is repulsive at the surface causing N ~ 0.5.
6Li + 208Pb EB = 30 MeV
Sakuragi, Phys. Rev. C35, 2161 (1987)
Normalization of folding potential and threshold anomaly
• An experiment done at near-barrier energies.
6Li + 208Pb7Li + 208Pb
N. Keeley et al, Nucl. Phys. A571, 326 (1994)
Threshold anomaly No threshold anomaly
Simultaneous χ2 analyses using extended optical model
Simultaneous:- elastic scattering, - semi-experimental direct reaction, - fusion cross section data
Extended optical model: two types of complex polarization potentials;DR and fusion potentials
Folding potential will not be adjusted. (N=1)
el/ R
F
DR
Search 4 parameters VF , WF , VD, and WD (in UF and UD)
χ2-fitting
Extended optical model
U = Vc – [V0 + UF + UDR ]Ui = Vi + iWi (i = F or DR)