Search for long-lived states in antiprotonic lithium

The spectrum of the (L_i^3 + p-bar + 2e) four-body system was calculated in an adiabatic approach. The two-electron energies were approximated by a sum of two single-electron effective charge two-center energies as suggested in [6]. While the structure of the spectrum does not exclude the existence of long-lived states, their experimental observability is still to be clarified

Precision Spectroscopy of Molecular Hydrogen Ions: Towards Frequency Metrology of Particle Masses

We describe the current status of high-precision ab initio calculations of the spectra of molecular hydrogen ions (H_2^+ and HD^+) and of two experiments for vibrational spectroscopy. The perspectives for a comparison between theory and experiment at a level of 1 ppb are considered.Comment: 26 pages, 13 figures, 1 table, to appear in "Precision Physics of Simple Atomic Systems", Lecture Notes in Physics, Springer, 200

Relativistic corrections of order m\alpha^6 to the two-center problem

Effective potentials of the relativistic m\alpha^6 order correction for the ground state of the Coulomb two-center problem are calculated. They can be used to evaluate the relativistic contribution of that order to the energies of hydrogen molecular ions or metastable states of the antiprotonic helium atom, where precision spectroscopic data are available. In our studies we use the variational expansion based on randomly chosen exponents that permits to achieve high numerical accuracy.Comment: 12 pages, 3 tables 2 figures; submitted to the Journal of Physics

Hyperfine structure of antiprotonic helium revealed by a laser-microwave-laser resonance method

Using a newly developed laser-microwave-laser resonance method, we observed a pair of microwave transitions between hyperfine levels of the $(n,L)=(37,35)$ state of antiprotonic helium. This experiment confirms the quadruplet hyperfine structure due to the interaction of the antiproton orbital angular momentum, the electron spin and the antiproton spin as predicted by Bakalov and Korobov. The measured frequencies of $\nu_{\text HF}^+ =12.89596 \pm 0.00034$ GHz and $\nu_{\text HF}^- =12.92467 \pm 0.00029$ GHz agree with recent theoretical calculations on a level of $6 \times10^{-5}$.Comment: 4 pages, 4 figures, 1 tabl

Обсуждение в ЦДУ РАН проблем развития отечественной статистики и путей их решения (обзор научных докладов и выступлений на секции статистики в 2018-2019 годах)

This scientific and information review provides insight into the contents and nature of some questions and matters of national statistics as noted in the reports of statisticians - academics and practitioners at the meeting of Statistics Section of the Central House of Scientists of the Russian Academy of Sciences (CDU RAS) in 2018-2019. The Section covered a wide range of topics which could be grouped (although this grouping is somewhat relative) into three focus areas in modern Russian statistics discussed in the 2018-2019 season at the Central House of Scientists: I. Theoretical and practical aspects associated with conducting statistical observations, II. Development issues of macroeconomic statistics and III. Application of international statistical standards to Russian conditions.In these respective areas, debates focused on the results of the 2016 Russian Census of agriculture, optimization of the organizational structure of the 2020 Russian Population Census based on the results of the 2018 Pilot Population Census, fundamental principles of consumer price monitoring and calculating the consumer price index in today’s Russian statistics. Topics of methodological support of statistics on non-financial economic assets, improving the quality of GDP estimates based on the development of annual supply and use tables, the subject matter of innovation statistics triggered heated discussions amongst the practitioners and theoreticians who participated actively in the meetings. Finally, the Section reviewed matters of adopting international statistical standards to suit Russian conditions, in particular, the practical implementation of the Resolution concerning statistics of work, employment, and labor underutilization and Russian issues of international banking statistics.В данной статье, подготовленной ее авторами в формате научно-информационного обзора, раскрываются содержание и характер отдельных проблем развития отечественной статистики, которые нашли свое отражение в докладах статистиков - ученых и практиков, выступавших на заседаниях секции статистики в Центральном Доме ученых Российской академии наук (ЦДУ РАН) в течение 2018-2019 гг. При всем разнообразии рассмотренных на секции статистики ЦДУ РАН вопросов можно было бы выделить (несмотря на определенную условность конкретно такой группировки) три следующих актуальных направления в современной отечественной статистике, дискуссии по которым проводились в очередном (2018-2019) сезоне работы Дома ученых: I. Теоретические и практические вопросы проведения статистических наблюдений; II. Вопросы развития макроэкономической статистики; III. Применение международных статистических стандартов в российских условиях.По данным направлениям в дискуссиях предметом обсуждения стали итоги Всероссийской сельскохозяйственной переписи 2016 г., вопросы оптимизации организационной схемы проведения Всероссийской переписи населения 2020 г. по итогам Пробной переписи населения 2018 г., основные принципы организации наблюдения за потребительскими ценами и расчета индекса потребительских цен в современной российской статистике. Широкий резонанс среди активно участвовавших в заседаниях секции специалистов - теоретиков и практиков вызвали обсуждения вопросов методологического обеспечения статистики нефинансовых экономических активов, повышения качества оценок ВВП на основе разработок ежегодных таблиц ресурсов и использования, проблематики статистики инноваций. И наконец, на секции дискутировались вопросы адаптации к российским условиям международных статистических стандартов, в частности результаты внедрения в статистическую практику Резолюции о статистике трудовой деятельности, занятости и недоиспользования рабочей силы и проблематика международной банковской статистики

Expert Assessment of a Ratio of Expenses at Construction of Oil Transport Infrastructure in the Arctic

When assessing the cost of construction and operation of transport infrastructure in the early stages of the investment process, there is a problem in the formalization of some indicators of the factors influencing decision-making. The temporary impossibility to express them in monetary or comparable natural quantities leads to uncertainty in the ratio between these two groups of factors. On the example of one of the discussed objects of oil transport infrastructure in the territory of the Russian Arctic, quantitative estimates of such uncertainties are obtained, the value of which was very weighty and variable depending on the considered alternative. The authors propose an approach based on the vector representation of factors, fuzzy set theory and expert estimates, which allows developing a criterion of the limit value of uncertainty, allowing making management decisions in the problems of choice. The corresponding model giving the possibility of calculation of such criterion is constructed

Resonant nuclear transition in the d-mu-Li6 muonic molecule

The reaction rate of the nuclear fusion d+Li6 ----> Be8*(2+,0) is estimated in the case where the nuclei are confined to each other by a muon. For the description of nuclear transitions, a method which is analogous to the Linear Combination of Atomic Orbitals has been used. Using the complex coordinate rotation method, we found that a molecular d-mu-Li6 state exists with energy (-20.3084-i0.0066) eV and |\Psi_{m}(0)|=0.44x10^{-7} fm^-3/2. The nuclear wave functions needed, were constructed in the form of antisymmetrized products of harmonic-oscillator functions for the three-cluster approximation, (dd\alpha), to the five-body (NNNN\alpha) problem. It was found that the reaction rate \lambda is strongly dependent on the energy gap between the d-Li6 threshold and the energy of the final Be8^* resonant state. The value of \lambda obtained by averaging over the width of this resonance, is 0.183x10^10 sec^{-1}.Comment: REVTEX, 63K, no postscripts, 21 pages, submitted to Phys.Rev.

Measurement of the e+e−→K+K−π+π−e^+e^- \to K^+K^-\pi^+\pi^- cross section with the CMD-3 detector at the VEPP-2000 collider

The process $e^+e^- \to K^+K^-\pi^+\pi^-$ has been studied in the center-of-mass energy range from 1500 to 2000\,MeV using a data sample of 23 pb$^{-1}$ collected with the CMD-3 detector at the VEPP-2000 $e^+e^-$ collider. Using about 24000 selected events, the $e^+e^- \to K^+K^-\pi^+\pi^-$ cross section has been measured with a systematic uncertainty decreasing from 11.7\% at 1500-1600\,MeV to 6.1\% above 1800\,MeV. A preliminary study of $K^+K^-\pi^+\pi^-$ production dynamics has been performed