Combined optical/X-ray study of the Galaxy cluster Abell 2256

Journal Article · Sun Jan 01 04:00:00 EST 1989 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/166995· OSTI ID:6286881

Fabricant, D G; Kent, S M; Kurtz, M J

The dynamics of Abell 2256 is investigated by combining X-ray observations of the intracluster gas with optical observations of the galaxy distribution and kinematics. Magnitudes and positions are presented for 172 galaxies and new redshifts for 75. Abell 2256 is similar to the Coma Cluster in its X-ray luminosity, mass, and galaxy density. Both the X-ray surface brightness and the galaxy surface density distributions exhibit an elliptical morphology. The radial galaxy distribution is steeper than the density profile of the X-ray-emitting gas, yet the galaxy velocity dispersion is higher than the equivalent value for the gas. Under the simplest assumptions that the galaxy velocity distribution is isotropic and the gas is isothermal, the galaxies and gas cannot be in hydrostatic equilibrium in a common gravitational potential. Models consistent with available data have mass-to-light ratios which increase with radius and galaxy orbits that are anisotropic with a radial bias. 39 references.

• Research Organization: Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (USA)
• OSTI ID: 6286881
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 336; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CONFIGURATION
COSMIC GASES
COSMIC RAY SOURCES
COSMIC X-RAY SOURCES
DENSITY
DISTRIBUTION
DYNAMICS
ELECTROMAGNETIC RADIATION
ELLIPTICAL CONFIGURATION
FLUIDS
GALAXY CLUSTERS
GASES
INTERGALACTIC SPACE
IONIZING RADIATIONS
LUMINOSITY
MASS
MECHANICS
MORPHOLOGY
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RADIATIONS
RED SHIFT
SPACE
SPATIAL DISTRIBUTION
VELOCITY
VISIBLE RADIATION
X RADIATION