Phys.Rev. C 100, 021301R (2019)

P.C.Ries, H.Pai, T.Beck, J.Beller, M.Bhike, V.Derya, U.Gayer, J.Isaak, B.Loher, Krishichayan, L.Mertes, N.Pietralla, C.Romig, D.Savran, M.Schilling, W.Tornow, S.Typel, V.Werner, J.Wilhelmy, A.Zilges, M.Zweidinger

Valence-shell dependence of the pygmy dipole resonance: E1 strength difference in ^{50, 54}Cr

NUCLEAR REACTIONS ^50,54Cr(γ, γ'), (polarized γ, γ'), E=7.5, 9.5 MeV bremsstrahlung beam from Darmstadt, and 5.5-9.8 MeV Compton-scattered polarized beam from TUNL; measured Eγ, Iγ, azimuthal angular distributions, integrated cross sections using nuclear resonance fluorescence (NRF) method at the Darmstadt High Intensity Photon Setup (DHIPS), and at the High-Intensity γ-ray Source facility (HIγS) of TUNL. ^50,54Cr; deduced levels, pygmy dipole resonances (PDR), J, π, widths of transitions to g.s., branching ratios, B(E1), B(M1), B(E2), Thomas-Reiche-Kuhn (TRK) energy-weighted sum rule for ^50,52,54Cr; calculated neutron skin thicknesses for ^{48,49,50,51,52,53,54,55,56}Cr.

doi: 10.1103/PhysRevC.100.021301