While the international nEDM collaboration at the Paul Scherrer Institut (PSI) took data in 2017 that covered a considerable fraction of the parameter space of claimed potential signals of ...hypothetical neutron (n) to mirror-neutron (n′) transitions, it could not test all claimed signal regions at various mirror magnetic fields. Therefore, a new study of n−n′ oscillations using stored ultracold neutrons (UCNs) is underway at PSI, considerably expanding the reach in parameter space of mirror magnetic fields (B′) and oscillation time constants (τnn′). The new apparatus is designed to test for the anomalous loss of stored ultracold neutrons as a function of an applied magnetic field. The experiment is distinguished from its predecessors by its very large storage vessel (1.47 m3), enhancing its statistical sensitivity. In a test experiment in 2020 we have demonstrated the capabilities of our apparatus. However, the full analysis of our recent data is still pending. Based on already demonstrated performance, we will reach sensitivity to oscillation times τnn′/cos(β) well above a hundred seconds, with β being the angle between B′ and the applied magnetic field B. The scan of B will allow the finding or the comprehensive exclusion of potential signals reported in the analysis of previous experiments and suggested to be consistent with neutron to mirror-neutron oscillations.
Ultracold neutrons were used to search for signals indicating the violation of Lorentz and CPT invariance or the existence of dark matter using the spectrometer to search for an electric dipole ...moment of the neutron.
Phys. Rev. C 100, 015502 (2019) We report on high-precision $Q_{\textrm{EC}}$ values of the
$^{21}$Na$\rightarrow^{21}$Ne and $^{23}$Mg$\rightarrow^{23}$Na mirror
$\beta$-transitions from mass ...measurements with ISOLTRAP at ISOLDE/CERN. A
precision of $\delta m/m = 9 \cdot 10^{-10}$ and $\delta m/m = 1.5 \cdot
10^{-9}$ was reached for the masses of $^{21}$Na and $^{23}$Mg, respectively.
We reduce the uncertainty of the $Q_{\textrm{EC}}$ values by a factor five,
making them the most precise experimental input data for the calculation of the
corrected $\mathcal{F} t$-value of these mixed Fermi/Gamow-Teller transitions.
For the $^{21}$Na$\rightarrow^{21}$Ne $Q_{\textrm{EC}}$ value, a $2.3 \sigma$
deviation from the literature $Q_{\textrm{EC}}$-value was found.
We report on high-precision \(Q_{\textrm{EC}}\) values of the \(^{21}\)Na\(\rightarrow^{21}\)Ne and \(^{23}\)Mg\(\rightarrow^{23}\)Na mirror \(\beta\)-transitions from mass measurements with ISOLTRAP ...at ISOLDE/CERN. A precision of \(\delta m/m = 9 \cdot 10^{-10}\) and \(\delta m/m = 1.5 \cdot 10^{-9}\) was reached for the masses of \(^{21}\)Na and \(^{23}\)Mg, respectively. We reduce the uncertainty of the \(Q_{\textrm{EC}}\) values by a factor five, making them the most precise experimental input data for the calculation of the corrected \(\mathcal{F} t\)-value of these mixed Fermi/Gamow-Teller transitions. For the \(^{21}\)Na\(\rightarrow^{21}\)Ne \(Q_{\textrm{EC}}\) value, a \(2.3 \sigma\) deviation from the literature \(Q_{\textrm{EC}}\)-value was found.
This case–control study was conducted to estimate the radiation‐induced risk of acute leukemia during the period from 1987 to 1997 among residents 0–5 years of age at the time of the Chernobyl ...accident in the most radioactively contaminated territories of the Ukraine (Rivno, Zhytomyr, Chernihiv and Cherkasy regions). Data were collected from 246 leukemia cases diagnosed between 1 January, 1987, and 31 December, 1997. Each case was verified and interviewed. Verified cases were compared to 492 randomly selected controls matched by age, sex, type of settlement (rural, semirural and urban) and administrative region of residency. The cumulative level of radiation exposure from the time of the Chernobyl accident to the date of diagnosis was assessed for each case and corresponding controls. Four dose‐range groups were selected for statistical analysis (0–2.9, 3–9.9, 10–99.9 and 100–313.3 mGy). The risk of leukemia was significantly increased (–2.4 95%CI: 1.4–4.0) among those with radiation exposure doses higher than 10 mGy (p = 0.01). The association between radiation exposure and risk was stronger among males (–2.8 95%CI: 1.4–5.5, p = 0.01), and for cases of acute leukemia that were diagnosed during the period from 1987 to 1992 (–2.5 95%CI: 1.2–5.1, p = 0.05), particularly acute myeloid leukemia (–5.8 95%CI: 1.4–24.6, p = 0.05). The influence of possible confounders and methods of selecting controls on the leukemia risk assessment was analyzed. The evaluated risk per unit dose is discussed.
The purpose of the research. The purpose of the article is to clarify the problems of higher legal education in relation to transformational processes that require legal regulation.Main content. It ...is determined that that it is the higher educational institution that is the main subject of training a law professional capable of performing complex tasks of the transformational stage of the state development. Methodology: Review of materials and methods based on the analysis of the Ukrainian legislation regulating higher legal education. Conclusions. Outlined are problems of higher legal education requiring application of better foreign experience.
The article discusses the issues of processing industrial hemp into goods for various functional purposes. Particular attention is paid to the processing of hemp trusts into cellulose-containing ...semi-finished products, as well as to the analysis of the properties of cellulose-containing fibrous materials obtained from industrial hemp. Based on the results of the study of physical, mechanical and organoleptic characteristics of the obtained cellulose-containing semi-finished products, their suitability for the pulp and paper industry and other sectors of the national economy has been established. The presented research is relevant for the purpose of creating an own raw material base for pulp and paper enterprises and light industry enterprises.
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