has performed a set of absolute Fission Product Yield (FPY) measurements. Using monoenergetic neutron at energies between 0.5 and 14.8 MeV, the excitation functions of a number of fission products from 235 U, 238 U and 239 Pu have begun to be mapped out. This work has practical applications for the determination of weapon yields and the rate of burn-up in nuclear reactors, while also providing important insight into the fission process. Combining the use of a dual-fission ionization chamber and-ray spectroscopy, absolute FPYs have been determined for approximately 15 di↵erent fission products. The dual-fission chamber is a back-to-back ionization chamber system with a 'thin' actinide foil in each chamber as a monitor or reference foil. The chamber holds a 'thick' target in the center of the system such that the target and reference foils are of the same actinide isotope. This allows for simple mass scaling between the recorded number of fissions in the individual chambers and the number of fissions in the center thick target, eliminating the need for the knowledge of the absolute fission cross section and its uncertainty. The 'thick' target was removed after activation and-rays counted with well shielded High Purity Germanium (HPGe) detectors for a period of 1.5-2 months.

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The neutron radiative-capture cross section of 76 Ge was measured between 0.4 and 14.8 MeV using the activation technique. Germanium samples with the isotopic abundance of ∼86% 76 Ge and ∼14% 74 Ge used in the 0νββ searches by the GERDA and Majorana Collaborations were irradiated with monoenergetic neutrons produced at eleven energies via the 3 H(p, n) 3 He, 2 H(d, n) 3 He and 3 H(d, n) 4 He reactions. Previously, data existed only at thermal energies and at 14 MeV. As a by-product, capture cross-section data were also obtained for 74 Ge at neutron energies below 8 MeV. Indium and gold foils were irradiated simultaneously for neutron fluence determination. High-resolution γ -ray spectroscopy was used to determine the γ -ray activity of the daughter nuclei of interest. For the 76 Ge total capture cross section the present data are in good agreement with the TENDL-2013 model calculations and the ENDF/B-VII.1 evaluations, while for the 74 Ge(n, γ ) 75 Ge reaction, the present data are about a factor of two larger than predicted. It was found that the 74 Ge(n, γ ) 75 Ge yield in the High-Purity Germanium (HPGe) detectors used by the GERDA and Majorana Collaborations is only about a factor of two smaller than the 76 Ge(n, γ ) 77 Ge yield due to the larger cross section of the former reaction.

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E 2 decay strength of the M 1 scissors mode of The E2/M 1 multipole mixing ratio δ1→2 of the 1 + sc → 2 + 1 γ-ray decay in 156 Gd and hence the isovector E2 transition rate of the scissors mode of a well-deformed rotational nucleus has been measured for the first time. It has been obtained from the angular distribution of an artificial quasimonochromatic linearly polarized γ-ray beam of energy 3.07(6) MeV scattered inelastically off an isotopically highly-enriched 156 Gd target. The data yield first direct support for the deformation dependence of effective proton and neutron quadrupole boson charges in the framework of algebraic nuclear models. First evidence for a low-lying J π = 2 + member of the rotational band of states on top of the 1 + band head is obtained, too, indicating a significant signature splitting in the K = 1 scissors mode rotational band.Introduction. -Orbital out-of-phase oscillations of a coupled two-component many-body quantum system are generally called Scissors Modes (ScMs). A ScM has been discovered in deformed atomic nuclei [1]. It has later been identified in Bose-Einstein condensed gases [2,3] and is expected to occur in Fermi gases [4], in metallic clusters [5][6][7], and in deformed quantum dots [8]. ScMs are interesting quantum modes because their properties are sensitive to the restoring forces between the many-body subsystems. They inevitably break spherical symmetry and hence lead to a sequence of quantum states of the many-body system that form a rotational band.

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.

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