Formation and Evolution of Red Hδ-strong Galaxies in Distant Clusters: Two Different Evolutionary Paths to S0 Galaxies?

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

26

Galaxies: Clusters: General, Galaxies: Formation, Galaxies: Interactions, Galaxies: Ism, Galaxies: Structure

Scientific paper

We numerically investigate the spectrophotometric evolution of galaxies with a variety of different star formation histories and degrees of dust extinction in order to elucidate the origin of the ``red Hδ-strong'' (RHDS) galaxies-characterized by strong [EW(Hδ)>3 Å] Balmer line absorption but with colors as red as the dormant E/S0 systems-first observed in distant clusters of galaxies. Specifically, we investigate the evolution in the [(B-R), EW(Hδ)]-plane of two different galaxy models: a ``truncation'' model in which a galaxy with a declining star formation rate (typical of a normal spiral) has its star formation abruptly truncated, and a ``starburst'' model in which a galaxy undergoes a secondary burst of star formation that is abruptly halted. This leads to the following three main results: (1) Both models pass through the zone inhabited by the RHDS galaxies in this plane, but the ``truncation'' models cannot explain the most extreme cases, which have EW(Hδ)>6 Å. (2) The reddest RHDS galaxies can only be explained by ``truncation'' or ``starburst'' models that have very heavy dust extinction (Av>0.5 mag). (3) Irrespective of whether dust effects are included, the ``truncation'' models are incapable of reproducing the very blue (B-R<1.6) analogs of the RHDS galaxies. By comparing these results with recent Hubble Space Telescope-based morphological and ground-based spectroscopic studies of distant cluster galaxies, we propose that there are two possible different evolutionary paths for the transformation of cluster spirals into S0 galaxies.

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

Formation and Evolution of Red Hδ-strong Galaxies in Distant Clusters: Two Different Evolutionary Paths to S0 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 Formation and Evolution of Red Hδ-strong Galaxies in Distant Clusters: Two Different Evolutionary Paths to S0 Galaxies?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Formation and Evolution of Red Hδ-strong Galaxies in Distant Clusters: Two Different Evolutionary Paths to S0 Galaxies? will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1601995

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