On the Morphology of the HST Faint Galaxies

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

74

Galaxies: Evolution, Galaxies: Fundamental Parameters

Scientific paper

Deep imaging with the Hubble Space Telescope (HST) has revealed a population of rapidly evolving galaxies, which account for < 50% of the total counts at I <~ 22.5, are well distinct from the passively evolving normal ellipticals and spirals, and have morphologies that elude the traditional Hubble classification scheme. This classification has been derived from the morphological properties of local galaxies observed at optical wavelengths. Since galaxy morphology is a function of the wavelength and of the localization and intensity of the star-formation activity, the appearance of galaxies at large redshifts is subject to k- correction and evolutionary effects of the stellar populations, even if the underlying dynamics does not change significantly. In addition, the strong dependence of the surface brightness on redshift as σ ~(1 +z)^-4^ implies that the observed morphology of distant galaxies is also affected by the limiting surface brightness that can be reached. This paper shows how local galaxies observed at UV wavelengths with the Ultraviolet Imaging Telescope (UIT) would appear to HST if placed at cosmological distances, with the UV light redshifted to the optical wavelengths. The simulated distant galaxies have morphologies that are of later type or more irregular than their local (optical) counterparts, and some are in qualitative agreement with those revealed by the faint HST surveys, suggesting that dynamical evolution has played a minor role in the evolution of the majority of the galaxies over a large fraction of the Hubble time. However, the dependence of galaxy morphology on the star-formation activity and on the wavelength must be properly understood before any conclusion on the overall morphological evolution of galaxies can be derived.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

On the Morphology of the HST Faint Galaxies 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 On the Morphology of the HST Faint Galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the Morphology of the HST Faint Galaxies will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1447548

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.