Nuclear resonance fluorescence in natural iron under a continuous-wave electron beam

Experiments on nuclear resonance fluorescence are carried out using bremsstrahlung with an end-point energy of 6.6 MeV from the continuous-wave electron beam of the Moscow Race-Track Microtron injector. Scattered photons are detected by a Ge(Li)-γ spectrometer. Results are presented for the 56Fe nucleus. The energies, widths of decay to the ground state, and reduced transition probabilities B(ML)↑ and B(EL)↑ are determined for several low-spin states. The magnetic dipole (M1) excitation with an energy of 3.449 MeV and the probability B(M1)↑ ∼ 1μ02 (μ0 is the nuclear magneton) is interpreted as an orbital (open-quotes scissorsclose quotes) mode. For the 56Fe nucleus considered as a symmetric rotator, the deformation parameter δ is found to range from 0.17 to 0.20. 18 refs., 3 figs., 1 tab