EDM: Neutron electric dipole moment measurement

An electric dipole moment (EDM) of the neutron would be a clear sign of new physics beyond the standard model of particle physics. The search for this phenomenon is considered one of the most important experiments in fundamental physics and could provide key information on the excess of matter versus antimatter in the universe. With high measurement precision, this experiment aims to ultimately achieve a sensitivity of 10-28 ecm, a 100-fold improvement in the sensitivity compared to the state-of-the-art. The EDM instrument is operated by an international collaboration based at the Technische Universität München

Frequency shifts in noble-gas magnetometers

Polarized nuclei are a powerful tool in nuclear spin studies and in searches for beyond-the-standard model physics. Noble-gas comagnetometer systems, which compare two nuclear species, have thus far been limited by anomalous frequency variations of unknown origin. We studied the self-interactions in a $^3$He-$^{129}$Xe system by independently addressing, controlling and measuring the influence of each component of the nuclear spin polarization. Our results directly rule out prior explanations of the shifts, and demonstrate experimentally that they can be explained by species dependent self-interactions. We also report the first gas phase frequency shift induced by $^{129}$Xe on $^3$He.Comment: v.

Towards an electrostatic storage ring for fundamental physics measurements

We describe a new table-top electrostatic storage ring concept for $30$ keV polarized ions at frozen spin condition. The device will ultimately be capable of measuring magnetic fields with a resolution of 10$^{-21}$ T with sub-mHz bandwidth. With the possibility to store different kinds of ions or ionic molecules and access to prepare and probe states of the systems using lasers and SQUIDs, it can be used to search for electric dipole moments (EDMs) of electrons and nucleons, as well as axion-like particle dark matter and dark photon dark matter. Its sensitivity potential stems from several hours of storage time, comparably long spin coherence times, and the possibility to trap up to 10$^9$ particles in bunches with possibly different state preparations for differential measurements. As a dark matter experiment, it is most sensitive in the mass range of 10$^{-10}$ to 10$^{-19}$ eV, where it can potentially probe couplings orders of magnitude below current and proposed laboratory experiments.Comment: 5 pages, 4 figures, contribution to the proceedings of the 8th International Symposium on Symmetries in Subatomic Physics (SSP2022

The Bose-Einstein Condensate and Cold Atom Laboratory

Microgravity eases several constraints limiting experiments with ultracold andcondensed atoms on ground. It enables extended times of flight withoutsuspension and eliminates the gravitational sag for trapped atoms. Theseadvantages motivated numerous initiatives to adapt and operate experimentalsetups on microgravity platforms. We describe the design of the payload,motivations for design choices, and capabilities of the Bose-Einstein Condensateand Cold Atom Laboratory (BECCAL), a NASA-DLR collaboration. BECCALbuilds on the heritage of previous devices operated in microgravity, featuresrubidium and potassium, multiple options for magnetic and optical trapping,different methods for coherent manipulation, and will offer new perspectives forexperiments on quantum optics, atom optics, and atom interferometry in theunique microgravity environment on board the International Space Station

Development of creep-resistant iron aluminides

Most studies of creep resistance in Fe-Al intermetallics are oriented at typical applications of 500-650 °C in competition with conventional stainless steels. These intermetallics show excellent oxidation and corrosion resistances even above 1000 °C, where conventional steels are no longer sufficiently resistant. This overview considers attempts at the development of good creep resistance for temperatures intermediate between these two temperature regimes. A variety of cast Fe3Al-based alloys containing solution or precipitate/dispersoid-forming additions will be reported. These alloys show good room temperature strength but weaken above 500 °C due to thermally activated deformation processes. It is shown to be difficult to improve creep strength by changing matrix diffusivity. Solution additions only slightly improve creep strength above 700 °C. Hardening in some alloys containing Fe2Nb Laves precipitates will be discussed. These materials show good strength to 700 °C, but the fine precipitates coarsen rapidly at higher temperatures. Carbide and boride additions generally show poor strengthening due coarse dispersoid distributions, but excellent thermal stability allows good strength retention to very low strain rates. As well as such alloying and structural factors, the importance of processing control to obtain the desired stable microstructures will be considered. © 2006 Elsevier B.V. All rights reserved.Peer Reviewe

Ultracold neutron storage in a bottle coated with the fluoropolymer CYTOP

The fluoropolymer CYTOP was investigated in order to evaluate its suitability as a coating material for ultracold neutron (UCN) storage vessels. Using neutron reflectometry on CYTOP-coated silicon wafers, its neutron optical potential was measured to be 115.2(2) neV. UCN storage measurements were carried out in a 3.8 l CYTOP-coated aluminum bottle, in which the storage time constant was found to increase from 311(9) s at room temperature to 564(7) s slightly above 10 K. By combining experimental storage data with simulations of the UCN source, the neutron loss factor of CYTOP is estimated to decrease from 1.1(1)$$\times 10^{-4}$$ to 2.7(2)$$\times 10^{-5}$$ at these temperatures, respectively. These results are of particular importance to the next-generation superthermal UCN source SuperSUN, currently under construction at the Institut Laue-Langevin, for which CYTOP is a possible top-surface coating in the UCN production volume