State-Insensitive Trapping of Alkaline-Earth Atoms in a Nanofiber-Based Optical Dipole Trap

Neutral atoms trapped in the evanescent optical potentials of nanotapered optical fibers are a promising platform for developing quantum technologies and exploring fundamental science, such as quantum networks and quantum electrodynamics. Building on the successful advancements with trapped alkali atoms, here we demonstrate a state-insensitive optical dipole trap for strontium-88, an alkaline-earth atom, using the evanescent fields of a nanotapered optical fiber. Leveraging the low laser-cooling temperatures of $\sim\!\!1~\mu$K readily achievable with strontium, we demonstrate trapping in record low trap depths corresponding to $\sim\!\!3~\mu$K. Further, employing a double magic wavelength trapping scheme, we realize state-insensitive trapping on the kilohertz-wide 5s^{2}\;^{1}\!S_{0}-5s5p\;^{3}\!P_{1,|m|=1} cooling transition, which we verify by performing near-surface high-resolution spectroscopy of the atomic transition. This allows us to experimentally find and verify the state insensitivity of the trap nearby a theoretically predicted magic wavelength of 435.827(25) nm. Given the non-magnetic ground state and low collisional scattering length of strontium-88, this work also lays the foundation for developing versatile and robust matter-wave atomtronic circuits over nanophotonic waveguides.Comment: 14 pages, 15 figure

Orbital structure of the meteor complex according to radar observations in Kazan. 1. Apparent distributions of aphelia

The results of an analysis of the orbital structure of the meteor complex accessible for radar observations at northern midlatitudes are reported. Experimentally, the study is based on the long-term monitoring of the influx of meteor matter into the Earth's atmosphere performed with the meteor radar of Kazan State University starting from 1986. The study uses a discrete quasi-tomographic method to measure the radiants and velocities of meteor showers based on goniometric data of the meteor radar and diffraction measurements of meteor velocities. The discretization of the detection environment-in particular, in terms of velocity-is shown to result in no substantial loss of measurement accuracy. The error of the measured velocity of the shower does not exceed 1.5 km/s for a standard deviation of a single velocity measurement equal to 3 km/s. Microshower representation is used with microshowers either representing the correlated part of the sporadic complex or being partial streams of major and minor showers, or fragments of the dust environment of minor bodies passing by Earth or falling onto it. The data of measurements made over the entire annual cycle are used to construct combined maps of the distribution of the observed 2263 microshowers (a total of 22 604 orbits) by their inclination, aphelion distance, and longitudes of the ascending nodes of their orbits. The observing conditions are shown to have a significant effect on the parameters of the distribution of aphelion distances for different months, and the corresponding distributions for prograde and retrograde orbits are shown to differ fundamentally. A specific feature of such distribution maps is that they allow uniform representation of both meteor showers and irregularities of the sporadic complex. © 2008 MAIK Nauka

General and special theory of the criminal process of Ukraine

Слінько, Д. С. Загальні та приватні теорії кримінального процесу України / Слінько Д. С., Слінько К. М., Філін Д. В. // Вісник Харківського національного університету імені В. Н. Каразіна. Сер.: Право. - 2021. - Вип. 31. - С. 92-98. - DOI: https://doi.org/10.26565/2075-1834-2021-31-13.Слінько, Д., Слінько, К., & Філін , Д. (2021). ЗАГАЛЬНІ І ПРИВАТНІ ТЕОРІЇ КРИМІНАЛЬНОГО ПРОЦЕСУ УКРАЇНИ. Вісник Харківського національного університету імені В. Н. Каразіна. Серія «Право», (31), 92-98. https://doi.org/10.26565/2075-1834-2021-31-13.Проаналізовано загальні і приватні спеціальні теорії кримінальногопроцесу України. Визначено положення його оптимізації та процесуальної економії на підставі єдиного змісту кримінальних і процесуальних норм при встановленні обставин, пов’язаних із закриттям кримінального провадження, звільнення особи від кримінальної відповідальності. Розкрито зміст кримінально процесуальних репресій, які визначені на основі процесуального статусу сторони обвинувачення і механізмі його застосування щодо окремої категорії учасників кримінального провадження. Відзначено, що приватна реперна теорія кримінального процесу може бути застосована в КПК України. Концептуальний підхід в даному випадку можна визначити виходячи з оптимізації, процесуальної економії кримінального процесу.The criminal process in Ukraine is based on thebasic principles of legal theories of Anglo-Saxon law. Adversarial proceedings are defined as a criminal lawsuit, on the basis of which the investigator is obliged to initiate criminal proceedings and support public prosecution. A retrospective analysis of the theoretical constructions of general theories of the criminal process in Ukraine shows their construction on the basis of Romano-Germanic provisions of continental Europe, where the basis is the publicity of the process and criminal prosecution by criminal justice authorities. In this case, the construction of general and particular theories of the process of Ukraine has a significant legal difference. The main differences can be considered on the basis of optimization constructions, procedural economy, application of criminal repressions connected with restriction of the rights, freedoms and interests of participants of criminal proceedings. It should be noted that the current criminal procedure law does not define, to the end, the concept of general and private theories of process. The article offerstheoretical aspects and practical solutions to emerging problems on the basis of the criminal process of Ukraine, the construction of theoretical approaches based on Anglo-Saxon law, which is important for optimizing the criminal process of Ukraine.Проанализированы общие и частные специальные теории уголовного процесса Украины. Определены положения его оптимизации и процессуальной экономии на основании единого содержания уголовных и процессуальных норм при установлении обстоятельств, связанных с закрытием уголовного производства, освобождения лица от уголовной ответственности. Раскрыто содержание уголовно-процессуальных репрессий, определенных на основе процессуального статуса стороны обвинения и механизме его применения в отношении отдельной категории участников уголовного производства. Отмечено, что частная реперная теория уголовного процесса применима в УПК Украины

Measurement of the K+→μ+νμγK^+\rightarrow{\mu^+}{\nu_{\mu}}{\gamma} decay form factors in the OKA experiment

A precise measurement of the vector and axial-vector form factors difference $F_V-F_A$ in the $K^+\rightarrow{\mu^+}{\nu_{\mu}}{\gamma}$ decay is presented. About 95K events of $K^+\rightarrow{\mu^+}{\nu_{\mu}}{\gamma}$ are selected in the OKA experiment. The result is $F_V-F_A=0.134\pm0.021(stat)\pm0.027(syst)$. Both errors are smaller than in the previous $F_V-F_A$ measurements.Comment: 9 pages, 8 figure

Experimental study of direct photon emission in K- --> pi- pi0 gamma decay using ISTRA+ detector

The branching ratio in the charged-pion kinetic energy region of 55 to 90 MeV for the direct photon emission in the K- --> pi- pi0 gamma decay has been measured using in-flight decays detected with the ISTRA+ setup operating in the 25 GeV/c negative secondary beam of the U-70 PS. The value Br(DE)=[0.37+-0.39(stat)+-0.10(syst)]*10^(-5) obtained from the analysis of 930 completely reconstructed events is consistent with the average value of two stopped-kaon experiments, but it differs by 2.5 standard deviations from the average value of three in-flight-kaon experiments. The result is also compared with recent theoretical predictions.Comment: 13 pages, 8 figure

Towards a high precision calculation for the pion-nucleus scattering lengths

We calculate the leading isospin conserving few-nucleon contributions to pion scattering on $^2$H, $^3$He, and $^4$He. We demonstrate that the strong contributions to the pion-nucleus scattering lengths can be controlled theoretically to an accuracy of a few percent for isoscalar nuclei and of 10% for isovector nuclei. In particular, we find the $\pi$-$^3$He scattering length to be $(62 \pm 4\pm 7)\times 10^{-3} m_{\pi}^{-1}$ where the uncertainties are due to ambiguities in the $\pi$-N scattering lengths and few-nucleon effects, respectively. To establish this accuracy we need to identify a suitable power counting for pion-nucleus scattering. For this purpose we study the dependence of the two-nucleon contributions to the scattering length on the binding energy of $^2$H. Furthermore, we investigate the relative size of the leading two-, three-, and four-nucleon contributions. For the numerical evaluation of the pertinent integrals, aMonte Carlo method suitable for momentum space is devised. Our results show that in general the power counting suggested by Weinberg is capable to properly predict the relative importance of $N$-nucleon operators, however, it fails to capture the relative strength of $N$- and $(N+1)$-nucleon operators, where we find a suppression by a factor of 5 compared to the predicted factor of 50. The relevance for the extraction of the isoscalar $\pi$-N scattering length from pionic $^2$H and $^4$He is discussed. As a side result, we show that beyond the calculation of the $\pi$-$^2$H scattering length is already beyond the range of applicability of heavy pion effective field theory.Comment: 24 pages, 14 figures, 10 table