2.5k citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Ilia State UniversityGE219 papers
- Instituto de Astrofísica de AndalucíaES90 papers
- Center for Astrophysics Harvard & SmithsonianUS82 papers
- Osservatorio Astrofisico di TorinoIT81 papers
- National Institute for AstrophysicsIT77 papers
- Boston UniversityUS72 papers
- Pulkovo ObservatoryRU71 papers
- Instituto de Astrofísica de CanariasES70 papers
- Space Research InstituteRU70 papers
- Centre National de la Recherche ScientifiqueFR69 papers
- Kansas State UniversityUS69 papers
- St Petersburg UniversityRU69 papers
23 papers · 1 filter
Hydrodynamic stability and mode coupling in Keplerian flows: local strato-rotational analysis
A. G. Tevzadze, G. D. Chagelishvili, J. -P. Zahn
Aims. Qualitative analysis of key (but yet unappreciated) linear phenomena in stratified hydrodynamic Keplerian flows: (i) the occurrence of a vortex mode, as a consequence of stra…
Dynamical feedback of the curvature drift instability on its saturation process
Z. Osmanov, D. Shapakidze, G. Machabeli
We investigate the reconstruction of pulsar magnetospheres close to the light cylinder surface to study the curvature drift instability (CDI) responsible for the twisting of magnet…
A method of open cluster membership determination
G. Javakhishvili, V. Kukhianidze, M. Todua +1
A new method for the determination of open cluster membership based on a cumulative effect is proposed. In the field of a plate the relative x and y coordinate positions of each st…
Amplification of compressional MHD waves in systems with forced entropy oscillations
B. M. Shergelashvili, C. Maes, S. Poedts +1
The propagation of compressional MHD waves is studied for an externally driven system. It is assumed that the combined action of the external sources and sinks of the entropy resul…
Transient growth and coupling of vortex and wave modes in self-gravitating gaseous discs
G. R. Mamatsashvili, G. D. Chagelishvili
Flow nonnormality induced linear transient phenomena in thin self-gravitating astrophysical discs are studied in the shearing sheet approximation. The considered system includes tw…
Stability and nonlinear adjustment of vortices in Keplerian flows
G. Bodo, A. Tevzadze, G. Chagelishvili +3
We investigate the stability, nonlinear development and equilibrium structure of vortices in a background shearing Keplerian flow. We make use of high-resolution global two-dimensi…
The WEBT Campaign on the Blazar 3C279 in 2006
M. Boettcher
The quasar 3C279 was the target of an extensive multiwavelength monitoring campaign from January through April 2006, including an optical-IR-radio monitoring campaign by the Whole…
Doppler shift oscillations in solar spicules
T. V. Zaqarashvili, E. Khutsishvili, V. Kukhianidze +1
Consecutive height series of Ha spectra in solar limb spicules taken on the 53 cm coronagraph of Abastumani Astrophysical Observatory at the heights of 3800-8700 km above the photo…
Centrifugally driven electrostatic instability in extragalactic jets
Z. Osmanov
The stability problem of the rotation induced electrostatic wave in extragalactic jets is presented. Solving a set of equations describing dynamics of a relativistic plasma flow of…
On the reconstruction of a magnetosphere of pulsars nearby the light cylinder surface
Z. Osmanov, G. Dalakishvili, G. Machabeli
A mechanism of generation of a toroidal component of large scale magnetic field, leading to the reconstruction of the pulsar magnetospheres is presented. In order to understand twi…
The Plasma Emission Model of RX J1856.5-3754
N. Chkheidze, G. Machabeli
A spectral analysis of the nearby isolated neutron star RX J1856.5-3754 is presented. Applying the kinetic approach, the distribution functions of emitting electrons are derived an…
The Spectrum of Gravitational Radiation from Primordial Turbulence
Grigol Gogoberidze, Tina Kahniashvili, Arthur Kosowsky
Energy injection into the early universe can induce turbulent motions of the primordial plasma, which in turn act as a source for gravitational radiation. Earlier work computed the…
On over-reflection and generation of Gravito-Alfven waves in solar-type stars
Andria Rogava, Grigol Gogoberidze, Stefaan Poedts
The dynamics of linear perturbations is studied in magnetized plasma shear flows with a constant shearing rate and with gravity-induced stratification. The general set of linearize…
Torsional oscillations of longitudinally inhomogeneous coronal loops
T. V. Zaqarashvili, K Murawski
We explore the effect of an inhomogeneous mass density field on frequencies and wave profiles of torsional Alfven oscillations in solar coronal loops. Dispersion relations for tors…
Extra dimensions and Lorentz invariance violation
Viktor Baukh, Alexander Zhuk, Tina Kahniashvili
We consider effective model where photons interact with scalar field corresponding to conformal excitations of the internal space (geometrical moduli/gravexcitons). We demonstrate…
Quantifying shear-induced wave transformations in the solar wind
Grigol Gogoberidze, Andria Rogava, Stefaan Poedts
The possibility of velocity shear-induced linear transformations of different magnetohydrodynamic waves in the solar wind is studied both analytically and numerically. A quantitati…
Resonant energy conversion of 3-minute intensity oscillations into Alfven waves in the solar atmosphere
D. Kuridze, T. V. Zaqarashvili
Nonlinear coupling between 3-minute oscillations and Alfven waves in the solar lower atmosphere is studied. 3-minute oscillations are considered as acoustic waves trapped in a chro…
Spectral line width decrease in the solar corona: resonant energy conversion from Alfv{é}n to acoustic waves
T. V. Zaqarashvili, R. Oliver, J. L. Ballester
Observations reveal an increase with height of the line width of several coronal spectral lines probably caused by outwardly propagating Alfv{é}n waves. However, the spectral line…
Coupling between radial and torsional oscillations in a magnetized plasma and possible stellar applications
T. V. Zaqarashvili, G. Belvedere
The weakly non-linear interaction of slow magnetoacoustic and torsional Alfven waves propagating along an unperturbed poloidal magnetic field in a stellar interior is studied in th…
Rossby waves in "shallow water" magnetohydrodynamics
T. V. Zaqarashvili, R. Oliver, J. L. Ballester +1
The influence of a toroidal magnetic field on the dynamics of Rossby waves in a thin layer of ideal conductive fluid on a rotating sphere is studied in the "shallow water" magnetoh…
Excitation and conversion of electromagnetic waves in pulsar magnetospheres
G. Gogoberidze, G. Z. Machabeli, V. V. Usov
We demonstrate that nonlinear decay of obliquely propagating Langmuir waves into Langmuir and Alfven waves (L --> L'+A) is possible in a one-dimensional, highly relativistic, strea…
X-ray pulsar radiation from polar cap heated by back-flow bombardment
J. Gil, G. I. Melikidze, B. Zhang
We consider the problem of the thermal X-ray radiation from the hot polar cap of radio pulsars showing evidence of \EB subpulse drift in radio band. In our recent Paper I, using th…
The radio delay of the exceptional 3C 454.3 outburst. Follow-up WEBT observations in 2005-2006
M. Villata, C. M. Raiteri, M. F. Aller
In spring 2005 the blazar 3C 454.3 was observed in an unprecedented bright state from the near-IR to the hard X-ray frequencies. A mm outburst peaked in June-July 2005, and it was…