Extended rotation curves of high-luminosity spiral galaxies. IV - Systematic dynamical properties, SA through SC

1978 ◽  
Vol 225 ◽  
pp. L107 ◽  
Author(s):  
V. C. Rubin ◽  
N. Thonnard ◽  
W. K., Jr. Ford
1978 ◽  
Vol 226 ◽  
pp. 770 ◽  
Author(s):  
C. J. Peterson ◽  
M. S. Roberts ◽  
V. C. Rubin ◽  
W. K., Jr. Ford

1978 ◽  
Vol 224 ◽  
pp. 782 ◽  
Author(s):  
V. C. Rubin ◽  
W. K., Jr. Ford ◽  
K. M. Strom ◽  
S. E. Strom ◽  
W. Romanishin

1979 ◽  
Vol 84 ◽  
pp. 211-220 ◽  
Author(s):  
Vera C. Rubin

Rotation curves of high luminosity spiral galaxies are flat, to distances as great as r=49 kpc. This implies a significant mass at large r. Rotational velocities increase about 20 km/s across a spiral arm, as predicted by the density wave theory. By analogy, it is suggested that our Galaxy has a flat rotation curve out to r∼60 kpc, with V ∼ constant at near the solar rotational velocity, and m ∼7×1011 m⊙. Values of A and B imply that the sun is not located in a spiral arm.


1980 ◽  
Vol 5 ◽  
pp. 191-191
Author(s):  
V. C. Rubin

For a sample of 21 Sc galaxies with a wide range of luminosities, of radii, and of masses, W. K. Ford and I have obtained spectra and determined rotation curves. By their kinematical behavior in their central regions, the Sc’s can be separated into two groups. Some galaxies, generally small and of low luminosity, have shallow central velocity gradients, reflecting their low central masses and densities. Other galaxies, most often large ones of high luminosity, have steep central velocity gradients. One reason this separation by central velocity gradients is of interest is because these galaxies exhibit other significant spectral differences which go hand-in-hand with the kinematical differences.The small, low luminosity galaxies show emission lines of Hα and [NII], with nuclear Ha sharp and stronger than [NII], and little or no stellar nuclear continuum, just as conventional HII regions. In contrast, the high luminosity galaxies show broad nuclear emission, with [NII] stronger than Ha. These galaxies have a strong red stellar continuum, arising from a red stellar population. The cause of the Hα[NII] intensity reversal in the nuclei of some galaxies remains unknown. However, the strong [NII] emission in generally high luminosity galaxies with massive nuclei, nuclei which show strong red continua, suggests that [Nil] intensity correlates with nuclear luminosity, and in turn with the density and velocity properties of the nuclear populations. We would expect high velocity dispersions and high bulge luminosities for galaxies with strong nuclear [NII] and steep central velocity gradients.


1978 ◽  
Vol 77 ◽  
pp. 23-31 ◽  
Author(s):  
Edwin E. Salpeter

21cm observations at the Arecibo Observatory for 9 edge-on spiral galaxies are described. Flat rotation curves are found in most cases.


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