Related papers: Nanoparticles as a possible moderator for an ultra…
Two hypothesizes concerning interaction of neutrons with nanoparticles and having applications in the physics of ultracold neutron (UCN) were recently considered in ref. [Physics of Atomic Nuclei 65(3): 400 (2002)]; they were motivated by…
We propose a new method to form very cold neutron (VCN) beams collimated and monochromatic without usual losses of flux by three or more orders in magnitude due to narrow line cutting from energy and angular spectra. To this purpose…
Analyzing new experiments with ultracold neutrons (UCNs) we show that physical adsorption of nanoparticles/nano-droplets, levitating in high-excited states in a deep and broad potential well formed by van der Waals/Casimir-Polder (vdW/CP)…
Ultracold neutrons provide a unique tool for the study of neutron properties. An overview is given of the ultracold neutron (UCN) source at PSI, which produces the highest UCN intensities to fundamental physics experiments by exploiting the…
Ultracold neutrons (UCN) are free neutrons that can be stored in experimental setups for several minutes. Some of the most important properties of the neutron, such as its tiny permanent electric dipole moment and its beta decay lifetime,…
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…
We study possibility of efficient reflection of very cold neutrons (VCN) from powders of nanoparticles. In particular, we measured the scattering of VCN at a powder of diamond nanoparticles as a function of powder sample thickness, neutron…
Inelastic scattering of ultra cold neutrons on bubbles with the size of nanometers is considered. It is shown that neutron-bubble cross section is large and sensitive to different vibration modes of bubbles. This process could be used for…
The problem of possible application of an ultracold neutron (UCN) trap as a detector of dark matter particles with long-range radius of forces has been considered. Transmission of small recoil energy in scattering is a characteristic of…
General theory of neutron scattering (elastic and inelastic) is presented. It is applicable for the whole domain of slow neutrons and includes as limiting cases existing theories for thermal and cold neutrons and for elastic scattering of…
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 impact of nuclear physics theories on cooling of isolated neutron stars is analyzed. Physical properties of neutron star matter important for cooling are reviewed such as composition, the equation of state, superfluidity of various…
Physical adsorption of atoms, molecules and clusters on surface is known. It is linked to many phenomena in physics, chemistry, and biology. Usually the studies of adsorption are limited to the particle sizes of up to ~10^2-10^3 atoms.…
We study the heat capacity and neutrino emission reactions (direct and modified Urca processes, nucleon-nucleon bremsstrahlung, Cooper pairing of nucleons) in matter of supranuclear density of the neutron star cores with superfluid neutrons…
Ultra-cold neutrons (UCN), neutrons with energies low enough to be confined by the Fermi potential in material bottles, are playing an increasing role in measurements of fundamental properties of the neutron. The ability to manipulate UCN…
Cooling of neutron stars (NSs) with the cores composed of neutrons, protons, and electrons is analyzed. The main cooling regulators are discussed: opening of direct Urca process in a NS central kernel; superfluidity of nucleons in NS…
The concept of a small-scale, pulsed-proton accelerator based compact ultracold neutron (UCN) source is presented. The essential idea of the compact UCN source is to enclose a volume of superfluid $^{4}\mathrm{He}$ converter with a…
We study the formation of a superfluid condensate of neutrinos inside a neutrino cluster. The attractive interaction between neutrinos is mediated by a scalar boson which is lighter than a neutrino. We consider the appearance of neutrino…
We analyze accumulation of ultracold neutrons (UCN) in a superfluid-helium converter vessel surrounded by a magnetic multipole reflector. We solved the spin-dependent rate equation, employing formulas valid for adiabatic spin transport of…
Supernova cooling has long been used to constrain physics beyond the Standard Model, typically involving new mediators or dark matter (DM) particles that couple to nucleons or electrons. In this work, we show that the large density of…