Dry (i.e. dissipationless) merging has been proposed as the main driver of the observed size evolution of early-type galaxies (ETGs). The actual role of this mechanism is questioned by the tightness of the local stellar mass-size relation of ETGs. Combining this observed scaling law with simple merging models, which should bracket cosmologically motivated merging histories, we draw the following conclusions: 1) local massive ETGs can have assembled at most ~45% of their stellar mass via dry mergers; 2) extreme fine tuning is required for this to be the case.
Nipoti C. (2012). Dry mergers and the size evolution of early-type galaxies. SAN FRANCISCO : Astronomical Society of the Pacific.
Dry mergers and the size evolution of early-type galaxies
NIPOTI, CARLO
2012
Abstract
Dry (i.e. dissipationless) merging has been proposed as the main driver of the observed size evolution of early-type galaxies (ETGs). The actual role of this mechanism is questioned by the tightness of the local stellar mass-size relation of ETGs. Combining this observed scaling law with simple merging models, which should bracket cosmologically motivated merging histories, we draw the following conclusions: 1) local massive ETGs can have assembled at most ~45% of their stellar mass via dry mergers; 2) extreme fine tuning is required for this to be the case.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
