Related papers: UCN anomalous losses and the UCN capture cross-sec…
The capture of trapped ultracold neutrons (UCNs) by closed hydrogenous impurities within a solid coating of the trap is discussed as a possible cause of observed anomalously large losses of UCNs in solid material UCN traps. Then significant…
We comment on the paper `UCN anomalous losses and the UCN capture cross section on material defects' by A. Serebrov et al., Phys. Lett. A 335 (2005) 327 - 336. Data presented do not originate from these authors alone but were taken in…
We present correct solution of the problem about a scattering of the neutron on a point-like defect existing in a medium and show that this mechanism cannot explain anomalous losses of UCN in storage bottles.
In connection with the problem of anomalous losses of ultracold neutrons (UCN) in the storage in the material traps the measurements of quasi-elastic scattering of UCN in collisions with trap surface have been carried out. It was observed…
The most accurate neutron lifetime measurements now use the material or magnetic traps of ultracold neutrons (UCN). The precision of these experiments is determined by the accuracy of estimating the neutron loss rate. In material UCN traps…
Modeling the motion of ultracold neutrons (UCNs) is crucial for assessing their losses, accurately measuring their lifetime, and describing other experiments. In material traps, it is necessary to account not only for specular but also 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…
Molecules with hyperfine splitting of their rotational line spectra are useful probes of optical depth, via the relative line strengths of their hyperfine components.The hyperfine splitting is particularly advantageous in interpreting the…
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…
A cubic kilometer scale experiment has been proposed to detect cosmic neutrinos of energy from tens of GeV up to the highest energies observed for cosmic rays, around 10**20 eV, or possibly even beyond. Detection efficiencies depend…
Ultracold neutrons (UCN), stored in a cell with hard walls that is attached to, and therefore rotating with, the Earth, will experience non-inertial frame effects, resulting in a broadening of the UCN spectrum. A heating or cooling of the…
The reflectivity of ultracold neutron (UCN) guides produced with a dedicated technique called {\sc Replika} has been studied. The guides are made of nickel, where the surface quality was copied from a glass layer. This results in a surface…
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…
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…
We have reexamined the problem of $n-\bar n$ oscillations for ultra-cold neutrons (UCN) confined within a trap. It is shown that for up to $10^3$ collisions with the walls the process can be described in terms of wave packets. The exact…
The transparency of metal foils for ultracold neutrons (UCNs) plays an important role in the design of future high-density UCN sources, which will feed a number of fundamental physics experiments. In this work, we describe and discuss the…
With the use of theory developed earlier, bulk effects in ultracold neutron coherent inelastic scattering are considered both for solid and liquid target samples related to energy and momentum exchange with phonon and diffusion-like modes.…
All results of the neutron lifetime measurements performed in the last 20 years with the UCN storage method are in a good agreement. These results are consistent with the latest most accurate measurements of the neutron decay asymmetry…
Neutron-antineutron oscillation (nnbar-osc) is a baryon-number-violating process and a sensitive probe for physics beyond the Standard Model. Ultra-cold neutrons (UCNs) are attractive for nnbar-osc searches because of their long storage…
We study light diffraction in the periodically modulated ultrathin metal films both analytically and numerically. Without modulation these films are almost transparent. The periodicity results in the anomalous effects, such as suppression…