Microscopic calculations of double and triple giant resonance excitations in heavy ion collisions
Abstract
We perform microscopic calculations of the inelastic cross sections for the double and triple excitation of giant resonances induced by heavyion probes within a semiclassical coupledchannels formalism. The channels are defined as eigenstates of a bosonic quartic Hamiltonian constructed in terms of collective randomphase approximation phonons. Therefore, they are superpositions of several multiphonon states, also with different numbers of phonons, and the spectrum is anharmonic. The inclusion of (n+1) phonon configurations affects the states whose main component is a nphonon one and leads to an appreacible lowering of their energies. We check the effects of such further anharmonicities on the previously published results for the cross section for the double excitation of giant resonances (GR). We find that the only effect is a shift of the peaks toward lower energies, the double GR cross section being unmodified by the explicity inclusion of the threephonon channels in the dynamical calculations. The latter provide an important contribution to the cross section in the triple GR energy region, which, however, is still smaller than the experimental available data. The inclusion of fourphonon configurations in the structure calculations does not modify the results.
 Authors:
 I.N.F.N.Catania and Dipartimento di Fisica e Astronomia, Universita di Catania, Via S. Sofia 67, I95123 Catania (Italy)
 (Spain)
 (DSMCEA/IN2P3CNRS), B.P. 55027, F14076 Caen Cedex 5 (France)
 (France)
 Publication Date:
 OSTI Identifier:
 20864219
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 74; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevC.74.064614; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; COLLECTIVE MODEL; COUPLED CHANNEL THEORY; CROSS SECTIONS; EIGENSTATES; EXCITATION; GIANT RESONANCE; HAMILTONIANS; HEAVY ION REACTIONS; PHONONS; RANDOM PHASE APPROXIMATION; SEMICLASSICAL APPROXIMATION; VIBRATIONAL STATES
Citation Formats
Lanza, E. G., Catara, F., Andres, M. V., Chomaz, Ph., Fallot, M., Scarpaci, J. A., Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, Apdo 1065, E41080 Sevilla, GANIL, Subatech, 4 rue Alfred Kastler BP 20722, F44307 Nantes Cedex 3, and Institut de Physique Nucleaire, IN2P3CNRS, F91406 Orsay Cedex. Microscopic calculations of double and triple giant resonance excitations in heavy ion collisions. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVC.74.064614.
Lanza, E. G., Catara, F., Andres, M. V., Chomaz, Ph., Fallot, M., Scarpaci, J. A., Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, Apdo 1065, E41080 Sevilla, GANIL, Subatech, 4 rue Alfred Kastler BP 20722, F44307 Nantes Cedex 3, & Institut de Physique Nucleaire, IN2P3CNRS, F91406 Orsay Cedex. Microscopic calculations of double and triple giant resonance excitations in heavy ion collisions. United States. doi:10.1103/PHYSREVC.74.064614.
Lanza, E. G., Catara, F., Andres, M. V., Chomaz, Ph., Fallot, M., Scarpaci, J. A., Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, Apdo 1065, E41080 Sevilla, GANIL, Subatech, 4 rue Alfred Kastler BP 20722, F44307 Nantes Cedex 3, and Institut de Physique Nucleaire, IN2P3CNRS, F91406 Orsay Cedex. Fri .
"Microscopic calculations of double and triple giant resonance excitations in heavy ion collisions". United States.
doi:10.1103/PHYSREVC.74.064614.
@article{osti_20864219,
title = {Microscopic calculations of double and triple giant resonance excitations in heavy ion collisions},
author = {Lanza, E. G. and Catara, F. and Andres, M. V. and Chomaz, Ph. and Fallot, M. and Scarpaci, J. A. and Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, Apdo 1065, E41080 Sevilla and GANIL and Subatech, 4 rue Alfred Kastler BP 20722, F44307 Nantes Cedex 3 and Institut de Physique Nucleaire, IN2P3CNRS, F91406 Orsay Cedex},
abstractNote = {We perform microscopic calculations of the inelastic cross sections for the double and triple excitation of giant resonances induced by heavyion probes within a semiclassical coupledchannels formalism. The channels are defined as eigenstates of a bosonic quartic Hamiltonian constructed in terms of collective randomphase approximation phonons. Therefore, they are superpositions of several multiphonon states, also with different numbers of phonons, and the spectrum is anharmonic. The inclusion of (n+1) phonon configurations affects the states whose main component is a nphonon one and leads to an appreacible lowering of their energies. We check the effects of such further anharmonicities on the previously published results for the cross section for the double excitation of giant resonances (GR). We find that the only effect is a shift of the peaks toward lower energies, the double GR cross section being unmodified by the explicity inclusion of the threephonon channels in the dynamical calculations. The latter provide an important contribution to the cross section in the triple GR energy region, which, however, is still smaller than the experimental available data. The inclusion of fourphonon configurations in the structure calculations does not modify the results.},
doi = {10.1103/PHYSREVC.74.064614},
journal = {Physical Review. C, Nuclear Physics},
number = 6,
volume = 74,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}

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