Experimental investigation of fusion of {sup 7}Li+{sup 28}Si above the Coulomb barrier

Excitation functions for the above-barrier fusion cross sections are measured for the first time for the {sup 7}Li+{sup 28}Si system by two methods--the characteristic {gamma}-ray method and the evaporation {alpha} measurement method--in the energy range E{sub lab}=11.5-26 MeV. Experimental results are consistent and agree with each other, and the one-dimensional Barrier Penetration Model (BPM) predictions describe the data well up to twice the Coulomb barrier, but they overestimate the data by about 15-20% at higher energies.

[1]  A. J. Pacheco,et al.  Study of the Threshold Anomaly in the Scattering of Li Isotopes on 27Al , 2007 .

[2]  A. J. Pacheco,et al.  Absence of the threshold anomaly in the elastic scattering of the weakly bound projectile {sup 7}Li on {sup 27}Al , 2006 .

[3]  M. Hussein,et al.  New manifestation of the dispersion relation : Breakup threshold anomaly , 2006 .

[4]  S. Kailas,et al.  Influence of projectile α-breakup threshold on complete fusion , 2006, nucl-ex/0603024.

[5]  A. J. Pacheco,et al.  Fusion, reaction, and breakup cross sections of {sup 9}Be on a light mass target , 2005 .

[6]  M. Hussein,et al.  Breakup threshold anomaly: New manifestation of the dispersion relation , 2005, nucl-th/0502011.

[7]  R. M. Anjos,et al.  Uncertainties in the comparison of fusion and reaction cross sections of different systems involving weakly bound nuclei , 2005 .

[8]  J. Sida,et al.  No enhancement of fusion probability by the neutron halo of 6He , 2004, Nature.

[9]  M. Kokkoris,et al.  Elastic scattering of Li-7+Si-28 at near-barrier energies , 2004 .

[10]  I. Thompson,et al.  How does breakup influence the total fusion ofLi6,7at the Coulomb barrier? , 2003 .

[11]  A. S. Toledo,et al.  Near-barrier fusion of weakly bound6Liand7Linuclei with59Co , 2003 .

[12]  D. Karamanis,et al.  The elastic scattering of 6Li+28Si at near-barrier energies , 2003 .

[13]  A. J. Pacheco,et al.  Fusion of stable weakly bound nuclei with 27 Al and 64 Zn , 2002 .

[14]  A. S. Toledo,et al.  Fusion hindrance in light nuclear systems: binding energy and/or surface diffuseness effect? , 2000 .

[15]  N. Added,et al.  Fusion and elastic scattering of 9 Be+ 64 Zn: A search of the breakup influence on these processes , 2000 .

[16]  Durand,et al.  Large enhancement of the sub-barrier fusion probability for a halo nucleus , 2000, Physical review letters.

[17]  K. Hagino,et al.  Role of breakup processes in fusion enhancement of drip-line nuclei at energies below the Coulomb barrier , 1999, nucl-th/9908012.

[18]  K. Hagino,et al.  A program for coupled-channel calculations with all order couplings for heavy-ion fusion reactions , 1999, nucl-th/9903074.

[19]  A. S. Toledo,et al.  Fusion versus breakup: observation of large fusion suppression for 9Be + 208Pb , 1999, nucl-ex/9901003.

[20]  B. Back,et al.  FUSION CROSS SECTIONS FOR THE PROTON DRIP LINE NUCLEUS 17F AT ENERGIES BELOW THE COULOMB BARRIER , 1998 .

[21]  C. Signorini Interaction at the barrier with unstable/loosely bound projectiles , 1997 .

[22]  M. M. Moura,et al.  IS FUSION INHIBITED FOR WEAKLY BOUND NUCLEI , 1997 .

[23]  F. Scarlassara,et al.  Fusion and breakup at the barrier with 11Be , 1996 .

[24]  A. Vitturi,et al.  Coulomb- and nuclear-induced break-up of halo nuclei at bombarding energies around the Coulomb barrier , 1996 .

[25]  S. Bhattacharya,et al.  7Li+12C and 7Li+13C fusion reactions at subbarrier energies , 1996 .

[26]  Hussein,et al.  Effect of Coulomb dipole polarizability of halo nuclei on their near-barrier fusion with heavy targets. , 1995, Physical review. C, Nuclear physics.

[27]  M. P. Pato,et al.  Fusion of halo nuclei , 1995 .

[28]  Dasso,et al.  Does the presence of 11Li breakup channels reduce the cross section for fusion processes? , 1994, Physical review. C, Nuclear physics.

[29]  R. Matheus,et al.  Complete fusion of 9Be + 29Si , 1993 .

[30]  Sagawa,et al.  Effect of breakup reactions on the fusion of a halo nucleus. , 1993, Physical review. C, Nuclear physics.

[31]  Hussein,et al.  Real part of the polarization potential for 11Li-induced fusion reactions. , 1993, Physical review. C, Nuclear physics.

[32]  S. Kailas,et al.  Fusion cross section for the system6Li+28Si atE ∼ 36 MeV , 1990 .

[33]  Coimbra,et al.  Effect of the entrance channel mass asymmetry on the limitation of light heavy-ion fusion cross sections. , 1990, Physical review. C, Nuclear physics.

[34]  L. Jarczyk,et al.  Fusion and direct reactions for strongly and weakly bound projectiles , 1981 .

[35]  A. Gavron Statistical model calculations in heavy ion reactions , 1980 .

[36]  T. H. Braid,et al.  Systematics of carbon- and oxygen-induced fusion on nuclei with 12 ≤ A ≤ 19 , 1979 .

[37]  F. Pühlhofer On the interpretation of evaporation residue mass distributions in heavy-ion induced fusion reactions , 1977 .