The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
Jozef Klačka - One of the best experts on this subject based on the ideXlab platform.
-
The non-Radial Component of the solar wind and motion of dust near mean motion resonances with planets
Astronomy & Astrophysics, 2008Co-Authors: Jozef Klačka, L. Komar, P. Pastor, J. PetržalaAbstract:We investigate the effect of solar wind and solar electromagnetic radiation on the dynamics of spherical cosmic dust particles. We also consider the non-Radial Component of the solar wind velocity, in the reference frame of the Sun. We apply the equation of motion to the motion of dust grains near commensurability resonances with a planet – mean motion orbital resonance (MMR; a particle is in resonance with a planet when the ratio of their mean motions is approximately the ratio of two small integers) – and possible capture of the grains in the resonances. Up to now, only nonspherical grains, under action of the electromagnetic radiation of the central star, were known to exhibit an increase of semimajor axis before capture into the MMR. This paper shows that the same result can be generated by the non-Radial Component of the solar wind even for spherical dust particles. Spherical dust grains enable the treatment of the problem in an analytic way (at least partially), which is not the case for the effect of electromagnetic radiation on nonspherical dust grains. The situation treated in the paper presents the second known case when resonant trapping of a cosmic body occurs for diverging orbits. The paper presents the first case of secular evolution of the eccentricity of a body captured in the resonance derived in an analytic way for a body characterized by a diverging orbit.
-
Solar Wind and Motion of Meteoroids
Dynamics of Natural and Artificial Celestial Bodies, 2001Co-Authors: Jozef KlačkaAbstract:The effect of solar wind on the orbital evolution of meteoroids is discussed. It is shown that results presented in recently published papers are incorrect. Non-Radial Component of solar wind is discussed from the qualitative point of view. It is shown that the orientation of non-Radial Component is opposite in comparison with the direction used in papers dealing with orbital evolution of meteoroids.
J. Petržala - One of the best experts on this subject based on the ideXlab platform.
-
The non-Radial Component of the solar wind and motion of dust near mean motion resonances with planets
Astronomy & Astrophysics, 2008Co-Authors: Jozef Klačka, L. Komar, P. Pastor, J. PetržalaAbstract:We investigate the effect of solar wind and solar electromagnetic radiation on the dynamics of spherical cosmic dust particles. We also consider the non-Radial Component of the solar wind velocity, in the reference frame of the Sun. We apply the equation of motion to the motion of dust grains near commensurability resonances with a planet – mean motion orbital resonance (MMR; a particle is in resonance with a planet when the ratio of their mean motions is approximately the ratio of two small integers) – and possible capture of the grains in the resonances. Up to now, only nonspherical grains, under action of the electromagnetic radiation of the central star, were known to exhibit an increase of semimajor axis before capture into the MMR. This paper shows that the same result can be generated by the non-Radial Component of the solar wind even for spherical dust particles. Spherical dust grains enable the treatment of the problem in an analytic way (at least partially), which is not the case for the effect of electromagnetic radiation on nonspherical dust grains. The situation treated in the paper presents the second known case when resonant trapping of a cosmic body occurs for diverging orbits. The paper presents the first case of secular evolution of the eccentricity of a body captured in the resonance derived in an analytic way for a body characterized by a diverging orbit.
Ednilton S. De Oliveira - One of the best experts on this subject based on the ideXlab platform.
-
Tidal forces in Reissner–Nordström spacetimes
The European Physical Journal C, 2016Co-Authors: Luís C. B. Crispino, Atsushi Higuchi, Leandro A. Oliveira, Ednilton S. De OliveiraAbstract:We analyze the tidal forces produced in the spacetime of Reissner–Nordstrom black holes. We point out that the Radial Component of the tidal force changes sign just outside the event horizon if the charge-to-mass ratio is close to 1, unlike in Schwarzschild spacetime of uncharged black holes, and that the angular Component changes sign between the outer and inner horizons. We solve the geodesic deviation equations for Radially falling bodies toward the charged black hole. We find, for example, that the Radial Component of the geodesic deviation vector starts decreasing inside the event horizon unlike in the Schwarzschild case.
-
Tidal Forces in Reissner-Nordstr\"om Spacetimes
arXiv: General Relativity and Quantum Cosmology, 2016Co-Authors: Luís C. B. Crispino, Atsushi Higuchi, Leandro A. Oliveira, Ednilton S. De OliveiraAbstract:We analyze the tidal forces produced in the spacetime of Reissner-Nordstr\"om black holes. We point out that the Radial Component of the tidal force changes sign just outside the event horizon if the charge-to-mass ratio is close to $1$ unlike in Schwarzschild spacetime of uncharged black holes, and that the angular Component changes sign between the outer and inner horizons. We solve the geodesic deviation equations for Radially falling bodies towards the charged black hole. We find, for example, that the Radial Component of the geodesic deviation vector starts decreasing inside the event horizon unlike in the Schwarzschild case.
Jean Arnaud - One of the best experts on this subject based on the ideXlab platform.
-
On the predominance of the Radial Component of the magnetic field in the solar corona
The Astrophysical Journal, 2001Co-Authors: Shadia Rifai Habbal, Richard Woo, Jean ArnaudAbstract:Polarimetric measurements of the corona out to 2 R☉ in the Fe XIII 10747 A line, the strongest of the iron forbidden lines, are placed for the first time in the context of spatially resolved images of coronal density structures. These measurements, which are the only tool currently available to yield the direction of the magnetic field, date to 1980, the only year when they were available with polarized brightness images of the corona. Through this comparison, the observed predominance of the Radial Component of the coronal magnetic field, discovered over three decades ago from eclipse observations and established systematically by Arnaud, is shown to point to the coexistence of two magnetic field Components in the corona: a nonRadial field associated with the large-scale structures known as streamers and a more pervasive Radial magnetic field. This finding suggests that these two Components are the coronal counterparts of the strong- and weak-field Components recently observed in the quiet-Sun photospheric field and supported by recent theoretical investigations of the solar dynamo.
Luís C. B. Crispino - One of the best experts on this subject based on the ideXlab platform.
-
Tidal forces in Reissner–Nordström spacetimes
The European Physical Journal C, 2016Co-Authors: Luís C. B. Crispino, Atsushi Higuchi, Leandro A. Oliveira, Ednilton S. De OliveiraAbstract:We analyze the tidal forces produced in the spacetime of Reissner–Nordstrom black holes. We point out that the Radial Component of the tidal force changes sign just outside the event horizon if the charge-to-mass ratio is close to 1, unlike in Schwarzschild spacetime of uncharged black holes, and that the angular Component changes sign between the outer and inner horizons. We solve the geodesic deviation equations for Radially falling bodies toward the charged black hole. We find, for example, that the Radial Component of the geodesic deviation vector starts decreasing inside the event horizon unlike in the Schwarzschild case.
-
Tidal Forces in Reissner-Nordstr\"om Spacetimes
arXiv: General Relativity and Quantum Cosmology, 2016Co-Authors: Luís C. B. Crispino, Atsushi Higuchi, Leandro A. Oliveira, Ednilton S. De OliveiraAbstract:We analyze the tidal forces produced in the spacetime of Reissner-Nordstr\"om black holes. We point out that the Radial Component of the tidal force changes sign just outside the event horizon if the charge-to-mass ratio is close to $1$ unlike in Schwarzschild spacetime of uncharged black holes, and that the angular Component changes sign between the outer and inner horizons. We solve the geodesic deviation equations for Radially falling bodies towards the charged black hole. We find, for example, that the Radial Component of the geodesic deviation vector starts decreasing inside the event horizon unlike in the Schwarzschild case.