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We report on time-modulated two-body weak decays observed in the orbital electron capture of hydrogenlike 140 Pr 59+ and 142 Pm 60+ ions coasting in an ion storage ring. Using non-destructive single ion, time-resolved Schottky mass spectrometry we found that the expected exponential decay is modulated in time with a modulation period of about 7 seconds for both systems. Tentatively this observation is attributed to the coherent superposition of finite mass eigenstates of the electron neutrinos from the weak decay into a two-body final state.

We report the observation of an interference between the electric dipole (E1) and the magnetic quadrupole (M2) amplitudes for the linear polarization of the Ly-α1 (2p3/2→1s1/2) radiation of hydrogenlike uranium. This multipole mixing arises from the coupling of the ion to different multipole components of the radiation field. Our observation indicates a significant depolarization of the Ly-α1 radiation due to the E1-M2 amplitude mixing. It proves that a combined measurement of the linear polarization and of the angular distribution enables a very precise determination of the ratio of the E1 and the M2 transition amplitudes and the corresponding transition rates without any assumptions concerning the population mechanism for the 2p3/2 state.

Using 98% linearly polarized radiation at the European Synchrotron Radiation Facility in Grenoble, the performance of a prototype two-dimensional microstrip Ge(i) detector for x-ray imaging and as a Compton polarimeter has been evaluated. Using the energy and position sensitivity of the detector, the ability to obtain a complete reconstruction of the Compton event has been demonstrated. The modulation coefficient of the polarimeter is in good agreement with the theoretical limit of a perfect detector.

We present the first observation of the 1s2p 3 P2 → 1s2s 3 S1 transition in He-like uranium. The experiment was performed at the internal gas-jet target of the ESR storage ring at GSI exploiting a Bragg crystal spectrometer and a germanium solid-state detector. Using the 1s 2 2p 2 P 3/2 → 1s 2 2s 2 S 1/2 transition in Li-like uranium as reference and the deceleration capabilities of the ESR storage ring, we obtained the first evaluation of the energy of an intra-shell transition for a He-like heavy ion.

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Decisions made by livestock producers inevitably determine the extent of actual farm animal welfare (FAW) provision in livestock production. This article identify key issues in the identification and empirical measurement of farmer's preferences for FAW‐related, non‐use values to encourage theoretically‐sound future research to address relevant potential producer trade‐off such as those between use and non‐use values with consequences for the total amount of FAW provisions to be delivered to society. Producer preferences for specific non‐use values, as well as their overall strength of preferences for non‐use values relative to use values will determine their provision of FAW. Investment and/or adjustment costs, however, may prevent producers from changing their production system to their preferred choice and economic welfare measures will be biased whenever such costs are neglected.

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