12 papers
The AGN-Disk Dynamics Connection
J. A. Sellwood, Juntai Shen
Any connection between central activity and the large-scale dynamics of disk galaxies requires an efficient mechanism to remove angular momentum from the orbiting material. The onl…
The Survival of Bars with Central Mass Concentrations
Juntai Shen, J. A. Sellwood
Many barred galaxies today harbor massive concentrations of gas in their centers, and some are known to possess supermassive black holes (SBHs) and their associated stellar cusps.…
Scattering of Stars by Transient Spiral Waves
J. A. Sellwood, Miguel Preto
Transient spiral waves of moderate amplitude cause substantial changes to the angular momenta of many stars in a galaxy disk. Stars near to corotation are affected most strongly: f…
Distinguishing Dark Matter from Modified Gravity
J. A. Sellwood, A. Kosowsky
Dynamical mass discrepancies in galaxies have two possible explanations: the existence of large amounts of dark matter or the breakdown of Newtonian gravity. True dark matter halos…
Disk heating and stellar migration in galaxies
J. J. Binney, J. A. Sellwood
The paper claimed that significant radial migration of stars in a stellar disk like that of the Milky Way could not occur. We now think that while the treatment of the effects of m…
Most Real Bars are Not Made by the Bar Instability
J. A. Sellwood
Having once thought that we understood how some galaxies were barred and had difficulty accounting for the absence of bars in others, it now seems that we have the opposite problem…