Polarized photon scattering offCr52: Determining the parity ofJ=1states

Abstract

The photoresponse of 52 Cr has been investigated in the energy range of 5.0 -9.5 MeV using the photon scattering technique at the HIγS facility of TUNL to complement previous work with unpolarized bremsstrahlung photon beams at the Darmstadt linear electron accelerator. The unambiguous parity determinations of the observed J = 1 states provides the basis needed to better understand the structure of the E1 and M 1 excitations. Theoretical calculations using the Quasiparticle Phonon Model incorporating self-consistent energy-density functional theory were performed to investigate the fragmentation pattern of the dipole strength below and around the neutron-emission threshold. These results compare very well with the experimental values.

Decay of quadrupole-octupole1−states inCa40andCe140Derya1, Tsoneva2, Aumann3 et al. 2016Phys. Rev. CSelf Cite12120View full textAdd to dashboardCite

“…142 Nd, and 144 Sm in the framework of a more advanced microscopic nuclear structure approach based on the self-consistent energy-density functional (EDF) theory and QPM including up to three-phonon configurations [18,19]. The theoretical method has been widely tested in systematic studies of electric and magnetic excitations from different energy and mass regions [4,8,10,12,16,17,65] and also in predictions of new modes of nuclear excitations related to the pygmy quadrupole resonance (PQR) [66][67][68]. A further advantage of the three-phonon EDF+QPM calculations is that we consider explicitly all one-phonon configurations up to the neutron threshold including explicitly the PDR.…”

“…In a simple macroscopic picture, a displacement of center-of-mass and center-ofcharge of the nucleus generates a vibrational motion trying to restore the proton-neutron symmetry. Nowadays, the rapidly increasing number of experiments using different probes and techniques allow for systematic studies of the PDR over isotopic and isotonic chains from different mass regions [4,[7][8][9][10][11][12][13][14][15][16][17]. A close connection between * derya@ikp.uni-koeln.de the total PDR strength and the amount of the neutron excess of neutron-rich nuclei which on the other hand is correlated with the neutron skin thickness was proposed [6,[18][19][20].…”

Exotic nuclear matter

“…The theoretical results have been used successfully to analyse the data of different experiments, e.g. [6,[8][9][10][11]13]. Although in many cases the overall features are already reasonably obtained by singlephonon QRPA calculations, multi-phonon effects are indispensable for a proper description of the fragmentation pattern and the total strength of pygmy modes [5].…”

“…Magnetic dipole excitations of the neutron skin in N=50 isotones, measured at the the High-Intensity γ-ray Source (HIγS) facility at Duke university, were investigated in [9,13]. Our calculations led to unexpected conclusion that the pygmy M1 strength 128 Sn.…”

“…In recent years nuclear density functional theory and nuclear many-body methods -ranging from HFB and (Q)RPA theory to the QPM approach of Soloviev et al -have been used to study systematically ground state properties and multipole response functions of exotic nuclei, especially in the region of the N = 82 and the Z = 50 shell closures, see e.g. [1] and detailed studies are found in [2][3][4][5][6][7][8][9][10][11][12][13][14]. None of those systems can be explored without an adequate reaction theory.…”