Related papers: Evidence for Secular Evolution in Late-Type Spiral…
Spiral structure in disk galaxies is modeled with nine collisionless N-body simulations including live disks, halos, and bulges with a range of masses. Two of these simulations make long-lasting and strong two-arm spiral wave modes that…
The morphologies of disk galaxies begin to deviate systematically from those of nearby galaxies at surprisingly low redshifts, possibly as low as z=0.3. This corresponds to a time ~3.5 Gyr in the past, which is only one quarter of the…
The environmental dependencies of the characteristics of spiral galaxy rotation curves are studied in this work. We use our large, homogeneously collected sample of 510 cluster spiral galaxy rotation curves to test the claim that the shape…
Since Edwin Hubble introduced his famous tuning fork diagram more than 70 years ago, spiral galaxies and early-type galaxies (ETGs) have been regarded as two distinct families. The spirals are characterized by the presence of disks of stars…
It is well established that many galaxies, like our Milky Way, exhibit spiral patterns. The entire galactic disc rotates about the galactic centre with different speeds; higher closer to the centre, lower at greater distances - that is,…
In order to establish an objective framework for studying galaxy morphology, we have developed a quantitative two-parameter description of galactic structure that maps closely on to Hubble's original tuning fork. Any galaxy can be placed in…
We study the neutral hydrogen properties of a sample of 20 bulgeless disk galaxies (Sd - Sdm Hubble types), an interesting class that can be used to constrain galaxy formation and evolution, especially the role of mergers versus internal…
We present I-band photometry, long-slit optical spectroscopy, and new aperture synthesis HI observations for eight late-type spirals with rotation velocities in the range 243 km/s < V_{rot} < 308 km/s. The sample will be used to study the…
(Abriged) This is a short review on the evolution of elliptical and lenticular/S0 galaxies in the dense environment of rich clusters for look-back times of more than half the age of the Universe. In addition, new data are presented for the…
Historically, galactic bulges are thought to be elliptical galaxy-like objects sitting in the middle of a generally larger disk. There are, however, more and more claims that some bulges are much more similar to disks. John Kormendy has…
The major axis and ellipse-fit intensity profiles of spiral galaxies larger than 0.3'' in the Hubble Space Telescope Ultra Deep Field (UDF) are generally exponential, whereas the major axis profiles in irregular disk galaxies, called…
This is the summary chapter of a review book on galaxy bulges. Bulge properties and formation histories are more varied than those of ellipticals. I emphasize two advances: 1 - "Classical bulges" are observationally indistinguishable from…
A simple model for the dust media describing evolution of the system like spiral galaxy is considered. In contrast to previous considerations we show that the initial density fold should be quasi-one-dimensional (bar-like) instead of…
We have analyzed the radial scales, central surface brightnesses, and colors of 404 disks of various types of galaxies. The central surface brightness mu0 and linear disk scale length h vary smoothly along the Hubble sequence of galaxies…
We present our project on galaxy evolution in the environment of distant rich clusters aiming at disentangling the importance of specific interaction and galaxy transformation processes from the hierarchical evolution of field galaxies.…
We have analyzed the redshift-dependent fraction of galactic bars over 0.2<z<0.84 in 2,157 luminous face-on spiral galaxies from the COSMOS 2-square degree field. Our sample is an order of magnitude larger than that used in any previous…
We study gravitational lensing by spiral galaxies, using realistic models consisting of halo, disk, and bulge components combined to produce a flat rotation curve. Proper dynamical normalization of the models is critical because a disk…
(Abridged) We analyze the evolution of 42 spiral galaxies in the Spitzer Infrared Nearby Galaxies Survey, using extinction-corrected UV, optical and near-infrared radial profiles to probe the emission of stars of different ages as a…
Stellar bars are important internal drivers of secular evolution in disk galaxies. Using a sample of nearby spiral galaxies with weak and strong bars, we explore the relationships between the star formation feature and stellar bars in…
In this paper we present the stellar population synthesis results for a sample of 75 bulges in isolated spiral Sb-Sc galaxies, using the spectroscopic data from the Sloan Digital Sky Survey and the STARLIGHT code. We find that both…