case western reserve university



Unraveling the Formation History of Elliptical Galaxies

T.J. Cox (CfA)

The idea that galaxies in general, and elliptical galaxies in particular, are shaped by their merger history has gained widespread acceptance. However, a detailed mapping between specific merger histories, and the wide variety of galaxies observed is still uncertain. By using a comprehensive set of numerical simulations, we show that a single disk-disk merger, as originally proposed by the "merger hypothesis," is a plausible mechanism to form many elliptical galaxies provided that dissipation is involved. We also show that additional (merger?) processes are likely needed to form th e largest ellipticals and we outline several properties commonly observed in elliptical galaxies that may provide insight into their formation history.