Asymptotic formulation of a differentially rotating star with small dissipation

1974 ◽  
Vol 26 (2) ◽  
pp. 305-317 ◽  
Author(s):  
Chao-Ho Sung
Keyword(s):  
Small Dissipation ◽  
Rotating Star ◽  
Asymptotic Formulation

scholarly journals Broadband Linear Polarization in Ap Stars

1993 ◽  
Vol 138 ◽  
pp. 305-309
Author(s):  
Marco Landolfi ◽  
Egidio Landi Degl’Innocenti ◽  
Maurizio Landi Degl’Innocenti ◽  
Jean-Louis Leroy ◽  
Stefano Bagnulo
Keyword(s):  
Magnetic Field ◽  
Circular Polarization ◽  
Linear Polarization ◽  
Rotation Axis ◽  
Spectral Lines ◽  
Line Of Sight ◽  
Long Time ◽  
Rotating Star ◽  
Ap Stars ◽  
The Magnetic Field

AbstractBroadband linear polarization in the spectra of Ap stars is believed to be due to differential saturation between σ and π Zeeman components in spectral lines. This mechanism has been known for a long time to be the main agent of a similar phenomenon observed in sunspots. Since this phenomenon has been carefully calibrated in the solar case, it can be confidently used to deduce the magnetic field of Ap stars.Given the magnetic configuration of a rotating star, it is possible to deduce the broadband polarization at any phase. Calculations performed for the oblique dipole model show that the resulting polarization diagrams are very sensitive to the values of i (the angle between the rotation axis and the line of sight) and β (the angle between the rotation and magnetic axes). The dependence on i and β is such that the four-fold ambiguity typical of the circular polarization observations ((i,β), (β,i), (π-i,π-β), (π-β,π-i)) can be removed.

scholarly journals Gravitational radiation from nonaxisymmetric instability in a rotating star

1994 ◽  
Vol 72 (9) ◽  
pp. 1314-1317 ◽  
Author(s):  
J. L. Houser ◽  
J. M. Centrella ◽  
S. C. Smith
Keyword(s):  
Gravitational Radiation ◽  
Rotating Star

Comment on ‘Propagation of solitary waves and shock wavelength in the pair plasma (J. Plasma Phys. 78, 525–529, 2012)’

2014 ◽  
Vol 80 (3) ◽  
pp. 513-516
Author(s):  
Frank Verheest
Keyword(s):  
Shock Wave ◽  
Solitary Wave ◽  
Solitary Waves ◽  
Plasma Phys ◽  
Theoretical Underpinning ◽  
Pair Plasma ◽  
Electrons And Positrons ◽  
Small Dissipation ◽  
Pseudopotential Approach ◽  
Wave Properties

In a recent paper ‘Propagation of solitary waves and shock wavelength in the pair plasma (J. Plasma Phys. 78, 525–529, 2012)’, Malekolkalami and Mohammadi investigate nonlinear electrostatic solitary waves in a plasma comprising adiabatic electrons and positrons, and a stationary ion background. The paper contains two parts: First, the solitary wave properties are discussed through a pseudopotential approach, and then the influence of a small dissipation is intuitively sketched without theoretical underpinning. Small dissipation is claimed to lead to a shock wave whose wavelength is determined by linear oscillator analysis. Unfortunately, there are errors and inconsistencies in both the parts, and their combination is incoherent.

scholarly journals The environment of the fast rotating star Achernar

2007 ◽  
Vol 474 (3) ◽  
pp. L49-L52 ◽  
Author(s):  
P. Kervella ◽  
A. Domiciano de Souza
Keyword(s):  
Rotating Star ◽  
Fast Rotating

On the Perturbations of a Nonrotating Star Excited by a Massive Source I.: The Matching Conditions at the Surface of the Star

1997 ◽  
Vol 06 (03) ◽  
pp. 323-339 ◽  
Author(s):  
V. Ferrari ◽  
L. Gualtieri
Keyword(s):  
Green’S Function ◽  
Green's Function ◽  
Function Method ◽  
Green’S Function Method ◽  
Matching Conditions ◽  
Rotating Star

In this paper we discuss the matching conditions to be imposed at the surface of a non-rotating star, when it is perturbed by a massive source, m0 ≪ M, either orbiting around the star or scattered by it. We shall determine the relations existing among the Regge–Wheeler and the Zerilli functions, which can be constructed by integrating the equations in the interior of the star, and the Bardeen–Press–Teukolsy and the Nakamura–Sasaki functions, which describe the perturbation outside the star, in the framework of the Newman–Penrose formalism. We shall also find the general form of the solution of the Nakamura–Sasaki equation appropriate to describe the problem on hand, by the Green's function method.

On Cluster Rotation in the Galactic Tidal Field

2014 ◽  
Vol 23 (3-4) ◽  
Author(s):  
Leonid P. Ossipkov
Keyword(s):  
Circular Orbit ◽  
Virial Theorem ◽  
Galactic Plane ◽  
Rotation Speed ◽  
Star Cluster ◽  
Rotating Star

AbstractThe dynamics of a rotating star cluster moving along a circular orbit in the axisymmetrical steady Galaxy is considered. The generalized tensor virial theorem allows to estimate its rotation speed. Conditions for direct and retrograde rotation in the galactic plane are found.

Sign in / Sign up

Export Citation Format

Share Document