Related papers: A next-generation inverse-geometry spallation-driv…
We installed a source for ultracold neutrons at a new, dedicated spallation target at TRIUMF. The source was originally developed in Japan and uses a superfluid-helium converter cooled to 0.9$\,$K. During an extensive test campaign in…
We present the results of an Ultracold neutron (UCN) production experiment in a pulsed neutron beam line at the Los Alamos Neutron Scattering Center. The experimental apparatus allows for a comprehensive set of measurements of UCN…
The ultracold neutron (UCN) source at Los Alamos National Laboratory (LANL), which uses solid deuterium as the UCN converter and is driven by accelerator spallation neutrons, has been successfully operated for over 10 years, providing UCN…
We report experiments on the production of ultracold neutrons (UCN) in a converter of superfluid helium coated with fluorinated grease. We employed our technique of window-free extraction of accumulated UCN from the helium, in which they…
Hypothetical short-range interactions could be detected by measuring the wavefunctions of ultracold neutrons (UCNs) on a mirror bounded by the Earth's gravitational field. The Searches require detectors with higher spatial resolution. We…
The paper considers the concept of an ultracold neutron source (UCN) based on the deceleration of very cold neutrons (VCN) by a local decelerating device. As the latter, it is proposed to use a gradient spin flipper. It is shown that in…
The wavelengths and energies of thermal and cold neutrons are ideally matched to the length and energy scales in the materials that underpin technologies of the present and future: ranging from semiconductors to magnetic devices, composites…
A new type of cold/ultracold neutron detector that can realize a spatial resolution of less than 100 nm was developed using nuclear emulsion. The detector consists of a fine-grained nuclear emulsion coating and a 50-nm thick $^{10}$B$_4$C…
Ultracold neutrons (UCN) can be stored in suitable bottles and observed for several hundreds of seconds. Therefore UCN can be used to study in detail the fundamental properties of the neutron. A new user facility providing ultracold…
Ultracold neutrons (UCNs) are used in experiments investigating fundamental interactions, testing the Standard Model of particle physics and searching for phenomena beyond it. Knowledge of the energy spectrum of UCNs is very often a key…
Ultra-cold neutrons (UCN) are neutrons with energies so low they can be stored in material bottles and magnetic traps. They have been used to provide the currently most accurate experiments on the neutron life time and electric dipole…
The European Spallation Source, currently under construction in Lund, Sweden, is a multidisciplinary international laboratory. Once completed to full specifications, it will operate the world's most powerful pulsed neutron source. Supported…
We investigate the possibility of ultracold neutron (UCN) storage in quantum states defined by the combined potentials of the Earth's gravity and the neutron optical repulsion by a horizontal surface of liquid helium. We analyse the…
Ultracold neutrons (UCNs) are key for precision studies of fundamental parameters of the neutron and in searches for new CP violating processes or exotic interactions beyond the Standard Model of particle physics. The most prominent example…
The Spallation Neutron Source (SNS) is being designed, constructed, installed and commissioned by the staff of six national laboratories, Argonne National Laboratory, Brookhaven National Laboratory, Jefferson National Accelerator…
Ultracold neutrons (UCN) have very low kinetic energies 0-300 neV, thereby can be stored in specific material or magnetic confinements for many hundreds of seconds. This makes them a very useful tool in probing fundamental symmetries of…
The dynamical structure factor of solid $^{15}$N$_{2}$ in the $\alpha$ phase ($T<35$K) is measured at the IN4 time-of-flight spectrometer at the Institut Laue Langevin, and the potential performance of this substance as a UCN converter is…
Ultracold neutrons (UCNs) are a useful tool for fundamental physics experiments. They can be used to probe the lifetime of free neutrons, search for new CP violating processes and exotic interactions beyond the Standard Model, perform…
Back-streaming neutrons from the spallation target of the China Spallation Neutron Source (CSNS) that emit through the incoming proton channel were exploited to build a white neutron beam facility (the so-called Back-n white neutron…
Cold neutrons are converted to ultra-cold neutrons (UCN) by the excitation of a single phonon or multiphonons in superfluid helium. The dynamic scattering function S(q, omega) of the superfluid helium strongly depends on pressure, leading…