Heidelberg 2015 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

HK: Fachverband Physik der Hadronen und Kerne

HK 25: Structure and Dynamics of Nuclei 5

HK 25.6: Vortrag

Dienstag, 24. März 2015, 16:00–16:15, T/HS2

Low-lying dipole strengths of ⁵⁰Cr^* — •H. Pai, T. Beck, J. Beller, U. Gayer, L. Mertes, N. Pietralla, P. Ries, C. Romig, V. Werner, and M. Zweidinger — Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt

Low-lying electric and magnetic dipole strengths (E1 and M1, respectively), particularly Pygmy Dipole Resonance (PDR) and Spin-flip M1 excitations, of atomic nuclei have drawn considerable attention in the last decade. The low-lying dipole strengths of ⁵⁰Cr were studied with the method of nuclear resonance fluorescence up to 9.7 MeV, using bremsstrahlung provided by the superconducting Darmstadt electron linear accelerator S-DALINAC. Twenty-four spin-1 states were observed between 3.0 and 9.7 MeV excitation energy, 17 of those for the first time. The excited states’ parities will be determined through polarized photon scattering at the High Intensity gamma ray Source (HIγS), Triangle Universities Nuclear Laboratory (TUNL) in Durham, NC, USA. Microscopic calculations within the quasiparticle-phonon nuclear model will be performed to interpret the dipole strength distribution of ⁵⁰Cr. The experimental results of ⁵⁰Cr will be compared to data on its closed-shell N = 28 isotone ⁵²Cr [1] and may provide information on the onset of the PDR in atomic nuclei.
*Supported by the DFG under contract No. SFB 634 and by the Helmholtz International Center for FAIR.
[1] H. Pai et al., Phys. Rev. C 88, 054316 (2013).