Observable properties of oblate spheroids

Abstract

view Abstract Citations (31) References (28) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Observable properties of oblate spheroids. Fillmore, J. A. Abstract Self-consistent solutions of the stellar hydrodynamic equations are presented for systems with isodensity surfaces which are concentric oblate spheroids and have constant mass-to-light ratios. Various models are investigated in order to determine whether observable parameters can distinguish the different configurations. Comparing velocity-dispersion measurements from both major and minor axes relative to the mean value can indicate the overall form of the velocity ellipsoid. The simulations indicate that observations can uniquely characterize those galaxies that lie at certain kinematic extremes, particularly those with excessive velocity dispersions in one component (e.g., tangential or radial). In restricted cases this diagnostic can put an upper limit on the true flattening of the spheroid. A contour diagram of the apparent angular velocity can readily illustrate rotation on spheroids versus on cylinders. M32 and the bulge of NGC 7814 appear to rotate on spheroids of roughly half the ellipticity of the isophotes, consistent with isotropic velocity dispersions. Publication: The Astronomical Journal Pub Date: May 1986 DOI: 10.1086/114086 Bibcode: 1986AJ.....91.1096F Keywords: Hydrodynamic Equations; Mass To Light Ratios; Oblate Spheroids; Self Consistent Fields; Stellar Models; Angular Velocity; Galactic Structure; Velocity Distribution; Astrophysics full text sources ADS | data products SIMBAD (9) NED (9)