Puffing up early-type galaxies by baryonic mass loss: numerical experiments

Details Puffing up early-type galaxies by baryonic mass loss: numerical experiments Puffing up early-type galaxies by baryonic mass loss: numerical experiments

2011-01-25

arxiv.org/abs/1101.4947v3

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

MNRAS, accepted 2011 March 07. Received 2011 February 25; in original form 2011 January 20

Scientific paper

Observations performed in the last few years indicate that most massive early-type galaxies (ETGs) observed at redshift z>1 exhibit sizes smaller by a factor of a few than local ETGs of analogous stellar mass. We present numerical simulations of the effect of baryonic mass loss on the structure of a spheroidal stellar system, embedded in a dark matter halo. This process, invoked as a possible explanation of the observed size increase of ETGs since z \sim 2, could be caused either by QSO/starburst driven galactic winds, promptly ejecting from Early Type Galaxies (ETGs) the residual gas and halting star formation (galactic winds), or by stellar mass returned to the ISM in the final stages of stellar evolution. Indeed, we find that a conceivable loss of about 50% of the baryonic mass can produce a significant size increase. However, the puffing up due to galactic winds occurs when the stellar populations are much younger than the estimated ages >0.5 Gyr of compact high-z ETGs. Therefore, while it may have had a role in deciding the final structure of ETGs, it cannot explain the evolution observed so far of their size-mass relation; its signature should be searched for in much younger systems. Conversely, the mass loss due to stellar evolution could cause a relatively modest expansion of passively evolving stellar systems later on, contributing to, without dominating, the observed evolution of their mass-size relationship.

Affiliated with

Also associated with

No associations

Rating

Puffing up early-type galaxies by baryonic mass loss: numerical experiments does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Puffing up early-type galaxies by baryonic mass loss: numerical experiments, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Puffing up early-type galaxies by baryonic mass loss: numerical experiments will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-418290