Research Interests: Nuclear Structure, Exotic Modes of Excitation, Nuclear Astrophysics, Exotic Nuclei, Effective Nuclear Interactions, Weak Interaction, Neutrino-Nucleus Reactions, Nonlinear Dynamics, Mathematical Modeling, Computational Physics


RESEARCH WORK

(see list of publications for recent work)


COMPLETED PROJECTS:

  • Nonlinear Dynamics of Giant Resonances 

  • Pygmy Dipole Resonances in Exotic Nuclei  

  • Relativistic Quasiparticle RPA  

  • Unitary correlation operator method  

  • Data Encryption with Nonlinear Physical Systems 

  • Chaotic and Regular Dynamics of Robot Model 



    • REVIEW: Exotic modes of excitation in atomic nuclei far from stability

    We review recent studies of the evolution of collective excitations in atomic nuclei far from the valley of beta - stability. Collective degrees of freedom govern essential aspects of nuclear structure, and for several decades the study of collective modes such as rotations and vibrations has played a vital role in our understanding of complex properties of nuclei. The multipole response of unstable nuclei and the possible occurrence of new exotic modes of excitation in weakly-bound nuclear systems, present a rapidly growing field of research, but only few experimental studies of these phenomena have been reported so far. Valuable data on the evolution of the low-energy dipole response in unstable neutron-rich nuclei have been gathered in recent experiments, but the available information is not sufficient to determine the nature of observed excitations. Even in stable nuclei various modes of giant collective oscillations had been predicted by theory years before they were observed, and for that reason it is very important to perform detailed theoretical studies of the evolution of collective modes of excitation in nuclei far from stability. We therefore discuss the modern theoretical tools that have been developed in recent years for the description of collective excitations in weakly-bound nuclei. The review focuses on the applications of these models to studies of the evolution of low-energy dipole modes from stable nuclei to systems near the particle emission threshold, to analyses of various isoscalar modes, those for which data are already available, as well as those that could be observed in future experiments, to a description of charge-exchange modes and their evolution in neutron-rich nuclei, and to studies of the role of exotic low-energy modes in astrophysical processes.

    N. Paar, D. Vretenar, E. Khan, and G. Colo, "Exotic modes of excitation in atomic nuclei far from stability", Rep. Prog. Phys. 70, 691 (2007).

List of Contents:

SUPPORTED BY:





"On the isoscalar-isovector splitting of pygmy dipole structures", by N. Paar, Y. F. Niu, D. Vretenar, and J. Meng, Phys. Rev. Lett. 103, 032502 (2009).
nucl-th/arXiv:0905.4848


"Neutrino and antineutrino charge-exchange reactions on 12C", by A. R. Samana, F. Krmpotic, N. Paar, and C. A. Bertulani, submitted to Phys. Rev. C (2010).
nucl-th/arXiv:1005.2134


"The quest for novel modes of excitation in exotic nuclei", by N. Paar, J. Phys. G: Nucl. Part. Phys. 37, 064014 (2010).
nucl-th/arXiv:1002.4776

REVIEW: Exotic modes of excitation in atomic nuclei far from stability by N. Paar, D. Vretenar,
E. Khan, and G. Colo,
Rep. Prog. Phys. 70, 691 (2007).                                                                      Review is focused towards modern theoretical models for studies of multipole response in unstable nuclei and possible occurrence of new exotic modes of excitation in weakly-bound nuclear systems. Of particular interest are low-energy dipole modes from stable nuclei to systems near the particle emission threshold, various isoscalar modes, charge exchange excitations and their evolution in neutron-rich nuclei, the role of exotic low-energy modes in astrophysical processes, etc.


University of Zagreb

The University of Zagreb is one of the oldest universities in Europe, it was officially founded on 23 September 1669 by Emperor and King Leopold I Habsburg who issued a decree granting the status and privileges of a university to the Jesuit Academy of the Royal Free City of Zagreb. In naturalist field the teaching started in 1896, with first lectures in mineralogy and geology, and then in botanic, physics, mathematics, chemistry, zoology and geography. Today, the University of Zagreb is the largest university in Croatia with more than 50000 full-time students.

Physics Department

The Physics department at the Faculty of Science has a long tradition in teaching and in scientific research. Since 1991, after moving to the new building on Horvatovac, the Department had its renaissance. The new equipment considerably improved the practical side of the education process and experimental research. Studies of the Departments theoretical physicists have led to new discoveries in the process of neleptonic decay, research of cosmology of neutrino, nuclear structures, theory of classic and quantum chaos, low dimensional systems, and electron dynamics on the surfaces of conductor and isolators. Since 2005, the Physics department consolidated its transition towards Bologna system of study programmes. Within the academic year around 700 students are pursuing one of the various theoretical, experimental, computational and educational physics programmes.