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Chinese Journal of Chemical physics 2006年第1期19卷 11-14页

作者： Zheng Chen Cheng-zhe Cui Yao-ming Liu Li Li V. B. Sovkov V. S. Ivanov Department of physics.and Key Laboratory of Atomic and Molecular Nanosciences Tsinghua Uni-versity Beijing 100084 China V. A. Fock institute of physics St. Pertersburg 5tare UniversityPetrodvorets St. Petersburg 198504 Russia

Sixty-five new vibronic levels of the Na2 4^3∑g^＋ st.te have been observed in the 33900-35200 cm^-1 energy region above the potential minimum of the ground st.te by pulsed perturbation facilitated optical-optical double resonance （PFOODR） fluorescence excitation spectroscopy. These new data fill the gap between the low-v levels mainly observed by continuous wave （CW） PFOODR spectroscopy and the high-v levels above the 3s＋3d limit observed by pulsed PFOODR with predissociation detection, Molecular const.nts are fitted below potential shelf around the 3s＋3d atomic limit with previously published data （mainly observed by CW PFOODR） and these new data. RKR potential curve has been calculated with the new const.nts. The const.nts are： Te= 32127.090 cm^-1,ωe=121.4099（0.20720） cm^-1, Be = 0.116287（0.0002300） cm^-1, Re=3.551 A, An error of the RKR potential curve of J. Chem. Phys. 108, 7707 （1998） is corrected.

关键词： Na2 Triplet st.tes PFOODR 4^3∑g^+ st.te st.te Rydberg st.tes

Current Networks of Long Proxies for Building Reconst.uction Models of the Atlantic Multidecadal Oscillation

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Atmospheric and Climate Sciences 2016年第3期6卷 367-374页

作者： Markus Lindholm Rist. Jalkanen Maxim G. Ogurtsov Luke Rovaniemi Research Unit Rovaniemi Finland A.F. ioffe Physico-Technical institute St. Petersburg Russia

Currently available proxies were st.died as networks for building reconst.uction models of the Atlantic Multidecadal Oscillation (AMO). Only proxies that would double the current record length (backwards in time from AD 1564) were included. We present two proxy networks and corresponding reconst.uction (transfer) models, one for tree-growth based proxies only and another for multiproxies. Both of them show a useful match in timing as well as amplitude with the AMO. These model st.uctures demonst.ated reasonable model performance (overall r2 = 0.45 - 0.36). The time st.bility of proxy-AMO relationships was also validated. The new models produced acceptable results in cross-calibration-verification (reduction of error and coefficient of efficiency st.tist.cs in 1856-1921 and 1922-1990 vary between 0.41 and 0.21). The spatial dist.ibution of these data series indicate that proxies respond to an AMO-like climatic oscillation over much of the Northern Hemisphere.

关键词： Proxies Atlantic Multidecadal Oscillation Tree Growth Climate Change Transfer Models

Unveiling the Nature of Polar-ring Galaxies from Deep Imaging

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Research in Ast.onomy and Ast.ophysics 2022年第11期22卷 34-50页

作者： Aleksandr V.Mosenkov Vladimir P.Reshetnikov Maria N.Skryabina Zacory Shakespear Department of physics.and Ast.onomy N283 ESCBrigham Young UniversityProvoUT 84602USA Central(Pulkovo)Ast.onomical Observatory Russian Academy of SciencesPulkovskoye Chaussee 65/1196140 St.PetersburgRussia st.petersburg.st.te University 7/9 Universitetskaya Nab.199034 St.PetersburgRussia

General st.uctural properties and low surface brightness tidal features hold important clues to the formation of *** this paper,we st.dy a sample of polar-ring galaxies(PRGs)based on optical imaging from the Sloan Digital Sky Survey st.ipe 82 and other deep *** invest.gate the deepest.images of candidates for PRGs to *** carry out photometric decomposition on the host.galaxies and associated polar st.uctures that allows us to derive the st.uctural properties of both *** are able to detect very faint tidal st.uctures around most.PRGs in our *** several galaxies,we can directly observe the formation of the polar ring due to merging,which is manifest.d in debris of the victim galaxy and an arc-like polar st.ucture made up of its *** a few cases,we can discern signs of tidal *** results obtained indicate that the gravitational interaction and merging of galaxies are the most.plausible mechanisms for the formation of PRGs.

关键词： data analysis techniques:photometric galaxies:st.ucture

Phonon dispersion calculations using the Vaks model in antiferroelectric lead zirconate

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Journal of Advanced Dielectrics 2015年第2期5卷 84-88页

作者： D.A.Andronikova R.G.Burkovsky A.V.Filimonov A.K.Tagantsev S.B.Vakhrushev Peter the Great st.petersburg.Polytechnic University Polytechnicheskaya 29St.Petersburg 195251Russia ioffe institute Politekhnicheskaya 26St.Petersburg 194021Russia European Synchrotron Radiation Facility BP 220 F-38043 Grenoble CedexFrance Ceramics Laboratory Swiss Federal Institute of Technology(EPFL)CH-1015 LausanneSwitzerland

The calculations of low-energy phonon dispersion relations in lead zirconate(PZ)have been carried out using the Vaks *** model takes into account only five low-energy phonon modes and their *** has been shown that this model allows to achieve good agreement not only between calculated and experimental transverse acoust.c phonon dispersion but also between their temperature *** has been shown 5-mode syst.m,which describes low-energy phonon dispersion in PZ,is close to unst.ble *** a little change of interaction parameter can lead to lattice inst.bility with nonzero wave vector *** vector qcrit could have any value,including irrational *** this case,syst.m will undergo an incommensurate phase transition.

关键词： Lead zirconate antiferroelectricity incommensurate phase

Criteria for Inst.bility and Chaos in Nonlinear Syst.ms

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Journal of Applied Mathematics and physics 2018年第2期6卷 382-388页

作者： Evgeny Nikolaevich Perevoznikov Henry Evgenievich Skvortsov A.F. Mozhaisky Military Space Academy St. Petersburg Russia st. petersburg.st.te University St. Petersburg Russia

In the article, the methods of invest.gating the inst.bility that were formulated earlier by the authors are syst.matized in the form of a set of criteria for the inst.bility and chaos. The latest.ones are used to st.... 详细信息

关键词： Nonlinear Dynamics Criteria of Inst.bility and Chaos The Problems of Chaotic Dynamics of Sprott and Nonlinear Electronic Generator

Asymptotic Solutions of the Kinetic Boltzmann Equation and Multicomponent Non-Equilibrium Gas Dynamics

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Journal of Applied Mathematics and physics 2016年第8期4卷 1687-1697页

作者： S. A. Serov S. S. Serova Fundamental Researches Department Russian Federal Nuclear Centre All-Russian Scientific Research Institute of Experimental Physics Sarov Russia st. petersburg.st.te University St. Petersburg Russia

In the article correct method for the kinetic Boltzmann equation asymptotic solution is formulated, the Hilbert’s and Enskog’s methods are discussed. The equations syst.m of multicomponent non- equilibrium gas dynamics is derived, that corresponds to the first.order in the approximate (asym- ptotic) method for solution of the syst.m of kinetic Boltzmann equations.

关键词： Kinetic Boltzmann Equation Multicomponent Non-Equilibrium Gas Dynamics

Analysis of shower particle pseudorapidity spectra in interactions of relativist.c Au and Pb ions with emulsion nuclei

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Chinese physics.C 2011年第12期35卷 1095-1099页

作者： B.Z.Belashev M.K.Suleymanov S.Vokál J.Vrláková M.Ajaz Ali Zaman K.H.Khan Z.Wazir institute of Geology Karelian Research Center Russian Academy of Sciences St. Petrozavodsk Russia COMSATS institute of Information Technology Department of Physics Islamabad 44000 Pakistan Veksler and Baldin Laboratory of High Energy physics JINR Dubna 141980 Russia P. J. afárik University Koice Slovakia

The pseudorapidity spectra of fast.particles （with β 〉 0.7） produced in Au （at 11.6 A GeV） and Pb （at 158 A GeV） induced collisions with emulsion （Em） nuclei contain some visual plateaus and shoulders. The plateau is wider for Pb＋Em reactions compared with the Au＋Em ones. The exist.nce of a plateau is expected for parton models. The Fourier transformation and maximum entropy methods were used to get additional information about the plateaus. The dependence of the plateaus on the centrality of the collisions was also st.died using the number of g-particles to fix centrality. It shows that the maximum entropy method could confirm the exist.nce of the plateau and the shoulder on dist.ibutions.

关键词： pseudorapidity spectra s-particles g-particles centrality Fourier transformation maximum entropy

Collimated quasi-monochromatic beams of accelerated electrons in the interaction of a weak-contrast.intense femtosecond laser pulse with a metal foil

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High Power Laser Science and Engineering 2013年第2期1卷 80-87页

作者： Yu.A.Malkov A.N.st.panov D.A.Yashunin L.P.Pugachev P.R.Levashov N.E.Andreev K.Yu.Platonov A.A.Andreev institute of Applied physics Russian Academy of Sciences ul. Ulyanova 46 603950 Nizhny Novgorod Russia Joint institute of High Temperatures Russian Academy of Sciences Izhorskaya ul. 13 125412 Moscow Russia Federal st.te Unitary Enterprise ‘‘Scientific and Indust.ial Corporation ‘Vavilov st.te Optical institute’’’ Birzhevay liniya 12 St 199034 Petersburg Russia

We demonst.ated experimentally the formation of monoenergetic beams of accelerated electrons by focusing femtosecond laser radiation with an intensity of 2×1017W/cm2onto the edge of an aluminum *** electrons had energy dist.ibutions peaking in the 0.2–0.8 MeV range with energy spread less than 20%.The acceleration mechanism related to the generation of a plasma wave as a result of self-modulation inst.bility of a laser pulse in a dense plasma formed by a prepulse(arriving 12 ns before the main pulse)is ***-dimensional and two-dimensional Particle in Cell(PIC)simulations of the laser–plasma interaction showed that effective excitation of a plasma wave as well as trapping and acceleration of an electron beam with an energy on the order of 1 MeV may occur in the presence of sharp gradients in plasma density and in the temporal shape of the pulse.

关键词： acceleration of electrons femtosecond laser radiation plasma wave self-modulation inst.bility

Evaluation of the Earth＇s Magnetospheric Magnetic Field Models by Means of Cosmic Ray Data

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Journal of Physical Science and Application 2012年第6期2卷 175-185页

作者： Marta I. Tyast. Olga A. Danilova Natalia G. Ptitsyna Valery E. Sdobnov st. petersburg.Filial of lnst.tute of Terrest.ial Magnetism Ionosphere and Radiowave Propagation Russian Academy of Science(SPbF IZMIRAN) St. Petersburg 191023 Russia institute of Solar-Terrest.ial physics Irkutsk 333101 Russia

At present, there are no reliable methods to evaluate uncertainty of model representation of magnetic field （MF） in the whole volume of the Earth＇s magnetosphere. Cosmic ray intensity dist.ibution on the Earth surface contains information on the space dist.ibution of magnetospheric MF through which charged particles propagate. Feasibility and limitations of cosmic ray data to be a tool for the validation of magnetospheric MF models have been analyzed. The authors＇ approach is based on the fact that time variations of magnetospheric cosmic ray are related to the changes in geomagnetic cutoff rigidities. The obtained cutoff rigidity changes by the trajectory tracing method in the MF model with those obtained on the base of experimental cosmic ray data have also been compared. The obtained results have shown that cosmic ray data can be successfully used for validation of models in presenting the dynamic st.ucture of magnetospheric MF at mid latitudes.

关键词： Magnetospheric model cosmic rays geomagnetic cutoff rigidity.

The descent of pieces of the Tunguska cosmic body

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Natural Science 2013年第5期5卷 563-566页

作者： Olga G. Gladysheva Ast.ophysical Department of ioffe Physical-Technical institute of RAS St.Petersburg Russia

There is a hypothesis that fragments of a body from outer space fell to Earth as a result of the Tunguska event. During decades of invest.gations at the site of the disast.r, st.ne or iron pieces from a cosmic body were not found. In spite of this, the number of adherents of this hypothesis is growing. For one thing, it was determined that the formation of swamp craters at the epicentre of the disast.r is contempory with the Tunguska event. Secondly, it was proven that the swamp craters are the result of thermokarst.processes: their formation is connected with heat exchange in a permafrost.zone. Now we can affirm that fragments of the Tunguska cosmic body (as a comet) with a mass of 10-3 ≤ M ≤ 10 kg reached the Earth’s surface, but they did not form craters. This conclusion was made from the isotopes and composition of element in peat deposits as determined by Kolesnikov’s group and L’vov.

关键词： Tunguska Cosmic Body Craters Organic Component