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Low-spin states of 157Dy have been studied using the JUROGAM II array, following the 155Gd ({\alpha}, 2n) reaction at a beam energy of 25 MeV. The level scheme of 157Dy has been expanded with four new bands. Rotational structures built on the [523]5/2- and [402]3/2+ neutron orbitals constitute new additions to the level scheme as do many of the inter- and intra-band transitions. This manuscript also reports the observation of cross I- to (I-1)- and I- to (I-1)+ E1 dipole transitions inter-linking structures built on the [523]5/2- (band 5) and [402]3/2+ (band 7) neutron orbitals. These interlacing band structures are interpreted as the bands of parity doublets with simplex quantum number s = -i related to possible octupole correlations., Comment: Published in Physical Review C (2019)

Isospin properties of dipole excitations in 74 Ge are investigated using the ({\alpha},{\alpha}'{\gamma}) reaction and compared to ({\gamma},{\gamma}) data. The results indicate that the dipole excitations in the energy region of 6 to 9 MeV adhere to the scenario of the recently found splitting of the region of dipole excitations into two separated parts: one at low energy, being populated by both isoscalar and isovector probes, and the other at high energy, excited only by the electromagnetic probe. Relativistic quasiparticle time blocking approximation (RQTBA) calculations show a reduction in the isoscalar E1 strength with an increase in excitation energy, which is consistent with the measurement., Comment: 7 pages, 7 figures

A recent publication (J.D. Anderson et. al., EPL 110, 1002) presented a strong correlation between the measured values of the gravitational constant $G$ and the 5.9-year oscillation of the length of day. Here, we provide a compilation of all published measurements of $G$ taken over the last 35 years. A least squares regression to a sine with a period of 5.9 years still yields a better fit than a straight line. However, our additions and corrections to the G data reported by Anderson {\it et al.} significantly weaken the correlation., Comment: 7 pages, 3 figures, 2 tables; fixed a few typos; accepted for publication in PRD

A detailed study of reciprocity failure in four 1.7 micron cutoff HgCdTe near-infrared detectors is presented. The sensitivity to reciprocity failure is approximately 0.1%\decade over up to five orders of magnitude in illumination intensity. The four detectors, which represent three successive production runs with modified growth recipes, show large differences in amount and spatial structure of reciprocity failure. Reciprocity failure could be reduced to negligible levels by cooling the detectors to about 110 K. No wavelength dependence was observed. The observed spatial structure appears to be weakly correlated with image persistence., Comment: 9 pages, 7 figures,3 tables

Flux dependent non-linearity (reciprocity failure) in HgCdTe near infrared detectors can severely impact an instrument's performance, in particular with respect to precision photometric measurements. The cause of this effect is presently not understood. To investigate reciprocity failure, a dedicated test system was built. For flux levels between 1 and 50,000 photons/s, a sensitivity to reciprocity failure of approximately 0.1%/decade was achieved. A wavelength independent non-linearity due to reciprocity failure of about 0.35%/decade was measured in a 1.7 micron HgCdTe detector., Comment: 7 pages, 8 figures

We report progress on a program of gravitational physics experiments using cryogenic torsion pendula undergoing large-amplitude torsion oscillation. This program includes tests of the gravitational inverse square law and of the weak equivalence principle. Here we describe our ongoing search for inverse-square-law violation at a strength down to $10^{-5}$ of standard gravity. The low-vibration environment provided by the Battelle Gravitation Physics Laboratory (BGPL) is uniquely suited to this study., Comment: To be published in The Proceedings of the Francesco Melchiorri Memorial Conference as a special issue of New Astronomy Reviews

Progress and plans are reported for a program of gravitational physics experiments using cryogenic torsion pendula undergoing large amplitude torsional oscillation. The program includes a UC Irvine project to measure the gravitational constant G and joint UC Irvine - U. Washington projects to test the gravitational inverse square law at a range of about 10 cm and to test the weak equivalence principle., Comment: 17 pages, 11 figures, contribution to the 10th Marcel Grossman Conference Proceedings (Rio de Janeiro, July 20 - 26, 2003) - changed wording in first paragraph of section 5