Probing quantum many-body dynamics with nuclei

Cedric Simenel, The Australian National University
Monday, Aug 07, 11:00 AM - Theory Seminar and Faculty Candidate
1200 FRIB Laboratory

Abstract:  The quantum many-body problem is common to all fields aiming at describing complex quantum systems of interacting particles. Examples range from quarks and gluons in a nucleon to macromolecules such as fullerenes. Nuclear systems are another example where up to about 500 nucleons (in the case of actinide collisions) may interact. What make nuclear systems special to test quantum many-body theories is their small size (few fermi) and short “native" time scale (few zeptoseconds) ensuring the complete isolation from external environment, and then, the preservation of quantum coherence during the dynamics. Nuclei are then ideal to investigate fundamental aspects of quantum physics such as coherence and tunnelling. Predicting the outcome of heavy-ion collisions is very challenging as several reaction mechanisms may occur. Ideally, the same theoretical model should be able to describe all the outcomes, e.g., (in)elastic scattering, multi-particle transfer, and fusion. A good starting point is to consider that the particles evolve independently in the mean-field generated by the ensemble of particles. This leads to the well known time-dependent Hartree-Fock (TDHF) theory proposed by Dirac. This microscopic approach and its extensions to incorporate pairing correlations as well as quantum fluctuations are well suited to investigate the variety of nuclear reactions. An appealing aspect is that structure and reaction are described on the same footing. In addition, the only input being the choice of the energy density functional, this approach provide a solid ground to predict reaction outomes with exotic nuclei. Recent applications to nuclear vibrations, particle transfer, fusion, and fission will be discussed in the talk.