Nonlinear classical model for the decay widths of isoscalar giant monopole resonances

Papachristou, PK; Mavrommatis, E; Constantoudis, V; Diakonos, FK; Wambach, J

dc.contributor.author	Papachristou, PK	en
dc.contributor.author	Mavrommatis, E	en
dc.contributor.author	Constantoudis, V	en
dc.contributor.author	Diakonos, FK	en
dc.contributor.author	Wambach, J	en
dc.date.accessioned	2014-03-01T01:28:52Z
dc.date.available	2014-03-01T01:28:52Z
dc.date.issued	2008	en
dc.identifier.issn	0556-2813	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/19004
dc.subject.classification	Physics, Nuclear	en
dc.subject.other	ONE-BODY DISSIPATION	en
dc.subject.other	DEPENDENT POTENTIAL WELL	en
dc.subject.other	INDEPENDENT-PARTICLE GAS	en
dc.subject.other	NUCLEAR-DYNAMICS	en
dc.subject.other	CHAOTIC DYNAMICS	en
dc.subject.other	BREATHING MODE	en
dc.subject.other	ATOMIC-NUCLEI	en
dc.subject.other	EXCITATION	en
dc.subject.other	PB-208	en
dc.subject.other	STABILITY	en
dc.title	Nonlinear classical model for the decay widths of isoscalar giant monopole resonances	en
heal.type	journalArticle	en
heal.identifier.primary	10.1103/PhysRevC.77.044305	en
heal.identifier.secondary	http://dx.doi.org/10.1103/PhysRevC.77.044305	en
heal.identifier.secondary	044305	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	The decay of the isoscalar giant monopole resonance (ISGMR) in nuclei is studied by means of a nonlinear classical model consisting of several noninteracting nucleons (particles) moving in a potential well with an oscillating nuclear surface (wall). The motion of the nuclear surface is described by means of a collective variable that appears explicitly in the Hamiltonian as an additional degree of freedom. The total energy of the system is therefore conserved. Although the particles do not directly interact with each other, their motions are indirectly coupled by means of their interaction with the moving nuclear surface. We consider as free parameters in this model the degree of collectivity and the fraction of nucleons that participate to the decay of the collective excitation. Specifically, we have calculated the decay width of the ISGMR in the spherical nuclei Pb208, Sm144, Sn116, and Zr90. Despite its simplicity and its purely classical nature, the model reproduces the trend of the experimental data that show that with increasing mass number the decay width decreases. Moreover the experimental results (with the exception of Zr90) can be well fitted using appropriate values for the free parameters mentioned above. It is also found that these values allow for a good description of the experimentally measured Sn112 and Sn124 decay widths. In addition, we give a prediction for the decay width of the exotic isotope Sn132 for which there is experimental interest. The agreement of our results with the corresponding experimental data for medium-heavy nuclei is dictated by the underlying classical mechanics, i.e., the behavior of the maximum Lyapunov exponent as a function of the system size. © 2008 The American Physical Society.	en
heal.publisher	AMER PHYSICAL SOC	en
heal.journalName	Physical Review C - Nuclear Physics	en
dc.identifier.doi	10.1103/PhysRevC.77.044305	en
dc.identifier.isi	ISI:000255457700023	en
dc.identifier.volume	77	en
dc.identifier.issue	4	en