scholarly journals A Tolman Surface Brightness Test for Universal Expansion and the Evolution of Elliptical Galaxies in Distant Clusters

1996 ◽  
Vol 456 (2) ◽  
Author(s):  
Michael A. Pahre, ◽  
S. G. Djorgovski, ◽  
R. R. de Carvalho
Keyword(s):  
Surface Brightness ◽  
Elliptical Galaxies ◽  
Universal Expansion

scholarly journals Surface brightness fluctuation distances for nearby dwarf elliptical galaxies

2001 ◽  
Vol 380 (1) ◽  
pp. 90-101 ◽  
Author(s):  
H. Jerjen ◽  
R. Rekola ◽  
L. Takalo ◽  
M. Coleman ◽  
M. Valtonen
Keyword(s):  
Surface Brightness ◽  
Elliptical Galaxies ◽  
Brightness Fluctuation ◽  
Dwarf Elliptical Galaxies

The Effect of Neutrinos on the Formation Time of Rich Clusters of Galaxies

1981 ◽  
Vol 4 (2) ◽  
pp. 181-182 ◽  
Author(s):  
B. M. Lewis
Keyword(s):  
Globular Clusters ◽  
Relaxation Mechanism ◽  
Elliptical Galaxies ◽  
Formation Time ◽  
Clusters Of Galaxies ◽  
Cluster Mass ◽  
Cluster Of Galaxies ◽  
Universal Expansion ◽  
Hubble Time

Both the radial and the velocity distributions of galaxies within rich clusters are well described by the isothermal distribution (e.g. Lewis 1978 and 1979). It is tempting to ascribe this apparently relaxed state to the operation of Lynden-BeU’s (1967) violent relaxation mechanism, during the initial coherent collapse on the proto-cluster, after it brakes itself against the universal expansion. This scenario explains the isothermal distribution observed in elliptical galaxies and globular clusters. When applied to a cluster of galaxies made up of baryons, however, the timescale for the scenario is comparable with the Hubble time H−1. The situation changes if most of the cluster mass is contributed by neutrinos.

scholarly journals Kinematic Modelling of NGC 3379

1983 ◽  
Vol 100 ◽  
pp. 295-296
Author(s):  
Gary A. Mamon
Keyword(s):  
Surface Brightness ◽  
Elliptical Galaxies ◽  
Anisotropic Pressure ◽  
Velocity Anisotropy ◽  
Kinematic Modelling

Giant elliptical galaxies are now known to be supported by anisotropic pressure rather than by rotation (cf. Binney, 1981). This anisotropy can be derived from observable quantities for spherical systems as was shown by Binney and Mamon (1982) in their study of M87. We investigate here the velocity anisotropy of the El galaxy NGC 3379, a giant elliptical whose surface brightness constitutes an excellent illustration of the r1/4 law.

scholarly journals The Manifold of Elliptical Galaxies

1987 ◽  
Vol 127 ◽  
pp. 79-88
Author(s):  
S. Djorgovski
Keyword(s):  
Galaxy Formation ◽  
Surface Brightness ◽  
Velocity Dispersion ◽  
Elliptical Galaxies ◽  
Morphological Parameters ◽  
Strong Regularity ◽  
Fundamental Plane ◽  
Global Properties ◽  
Error Bars ◽  
Intrinsic Scatter

Global properties of elliptical galaxies, such as the luminosity, radius, projected velocity dispersion, projected luminosity density, etc., form a two-dimensional family. This “fundamental plane” of elliptical galaxies can be defined by the velocity dispersion and mean surface brightness, and its thickness is presently given by the measurement error-bars only. This is indicative of a strong regularity in the process of galaxy formation. However, all morphological parameters which describe the shape of the distribution of light, and reflect dynamical anisotropies of stars, are completely independent from each other, and independent of the fundamental plane. The M/L ratios show only a small intrinsic scatter in a luminosity range spanning some four orders of magnitude; this suggests a constant fraction of the dark matter contribution in elliptical galaxies.

scholarly journals Starburst Feedback in Local, Massive Galaxies

2006 ◽  
Vol 2 (S235) ◽  
pp. 280-283
Author(s):  
Crystal L. Martin
Keyword(s):  
Surface Brightness ◽  
Milky Way ◽  
Velocity Dispersion ◽  
Rotation Speed ◽  
Far Infrared ◽  
Elliptical Galaxies ◽  
Evolutionary Path ◽  
Sky Surveys ◽  
Massive Galaxies ◽  
Stellar Velocity

Major mergers of gas-rich galaxies, each comparable in mass to the Milky Way, are rare at the present epoch. These events were readily identifed, however, two decades ago in far-infrared sky surveys (Soifer et al. 1986, 1987). Removal of the dust enshrouding these starbursts was almost immediately proposed as an evolutionary path to quasar formation (Sanders 1988). Recent measurements of the stellar velocity dispersion, rotation speed, and stellar surface brightness profile of these mergers suggest ULIRGs are indeed progenitors of field elliptical galaxies (Genzel et al. 2001; Tacconi et al. 2002).

scholarly journals Stellar Populations and Hubble Type

1983 ◽  
Vol 6 ◽  
pp. 187-190
Author(s):  
Sidney van den Bergh
Keyword(s):  
Strong Correlation ◽  
Globular Clusters ◽  
Surface Brightness ◽  
Stellar Populations ◽  
Elliptical Galaxies ◽  
Young Stars ◽  
Stellar Content ◽  
Clear Cut ◽  
Spiral Arm ◽  
Galaxy Morphology

Men are more apt to be mistaken in their generalization than in their particular observations. MachiavelliIt was already realized by Hubble (1936) that galaxy morphology and stellar content were correlated. He pointed out that resolution into stars increases along the classification sequence Sa-Sb-Sc. Simultaneously the colours of spirals become bluer and their integrated spectral types become earlier as one proceeds from Sa to Sc. Baade (1944) speculated that the red stars in ellipticals and in the nuclear bulges of spirals were identical to those in globular clusters. He suggested that stars in galaxies belong to two distinct populations: young metal-rich stars of Population I which inhabit the disc and spiral arm regions of spirals, and old metal-poor stars of Population II which dominate the light of elliptical galaxies and the nuclear bulges of spirals. Subsequently Baade (1950) emphasized the strong correlation between the occurrence of gas and dust and the presence of young stars. As Baade put it so succinctly “No dust, no Population I”. Belief in a clear cut dichotomy between Population I and Population II was strengthened by the differences in their radial luminosity distributions. The surface brightness of Population I in spirals is well represented by an exponential disc, whereas the surface brightness of Population II stars in ellipticals and the bulges of spirals may be described by an r1/4 law (de Vaucouleurs 1959).

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