相关论文: Evidence for Secular Evolution in Late-Type Spiral…
We review internal secular evolution in galaxy disks -- the fundamental process by which isolated disks evolve. We concentrate on the buildup of dense central features that look like classical, merger-built bulges but that were made slowly…
We present data for a sample of 45 spiral galaxies over a range of Hubble types, imaged in the near-IR J and K bands. Parameters are calculated describing the bulge, disk and bar K-band light distributions, and we look for correlations…
Through vertical resonances, bars can produce pseudo-bulges, within secular evolution. Bulges and pseudo-bulges have doubled their mass since z=1. The frequency of bulge-less galaxies at z=0 is difficult to explain, especially since clumpy…
The frequency of barred spiral galaxies as a function of redshift contains important information on the gravitational influence of stellar disks in their dark matter halos and also may distinguish between contemporary theories for the…
We present observations of pseudobulges in S0 and spiral galaxies using imaging data taken with the Spitzer Infra-Red Array Camera. We have used 2-d bulge-disk-bar decomposition to determine structural parameters of 185 S0 galaxies and 31…
Simulations and observations of galactic bars suggest they do not commonly evolve into bulges, although it is possible that the earliest bars formed bulges long ago, when galaxies were smaller, denser, and had more gas. The most highly…
We studied a sample of 58 edge-on spiral galaxies at redshifts $z \sim 1$ selected in the Hubble Ultra Deep Field. For all galaxies we analyzed the 2D brightness distributions in the $V_{606}$ and $i_{775}$ filters and measured the radial…
We examine whether early-type galaxies in clusters may have evolved from later types by the fading of their disks (e.g., as a result of ram-pressure stripping or strangulation) or by enhancement of the bulge luminosity (e.g., due to tidal…
New observations in favour of a significant role of secular evolution are reviewed: central star formation boosted in pseudo-bulge barred galaxies, relations between bulge and disk, evidence for rejuvenated bulges. Numerical simulations…
We study the photometric parameters of the bulges of galaxies of different Hubble types including ellipticals, lenticulars, early and late type spirals and early type dwarf galaxies. Analyzing the distributions of various photometric…
A bulge-disk decomposition is made for 737 spiral and lenticular galaxies drawn from a SDSS galaxy sample for which morphological types are estimated. We carry out the bulge-disk decomposition using the growth curve fitting method. It is…
The dynamical evolution of super star clusters (SSCs) moving in the background of a dark matter halo has been investigated as a possible event responsible for the formation of bulges in late-type spirals. The underlying physical processes…
The dynamical evolution of super star clusters (SSCs) moving in the background of a dark matter halo has been investigated as a possible event responsible for the formation of bulges in late-type spirals. The underlying physical processes…
We revisit the color bimodality of galaxies using the extensive EFIGI morphological classification of nearby galaxies. The galaxy SDSS images in the g, r and i bands are decomposed as bulge+disk using SourceXtractor++. The spectral energy…
We present observational evidence for a galaxy `Type' dependence to the location of a spiral galaxy's disk parameters in the mu_0-log(h) (central disk surface-brightness - disk scale-length) plane. With a sample of ~40 Low Surface…
We present line-strengths and kinematics from the central regions of 32 galaxies with Hubble types ranging from E to Sbc. Spectral indices, based on the Lick system, are measured in the optical and near infra-red (NIR). The 24 indices…
We have conducted a spectroscopic analysis of the bulges of a sample of 31 spiral galaxies, spanning the Hubble sequence from S0 to Scd type, in order to study the radial distribution of their stellar population properties.
One of the most outstanding questions in contemporary astrophysics is: What is the significance of galaxy morphology? What physical processes underlier the morphologies we observe and is a galaxy's internal structure driving its evolution…
Spiral galaxies offer a unique opportunity to study the role of star formation in galaxy evolution and to test various theoretical star formation schemes. I review some recent relevant work on the evolution of spiral galaxies. Detailed…
Self-gravitating systems evolve toward the most tightly bound configuration that is reachable via available evolution processes. The inner parts shrink and the outer parts expand, provided that some physical process transports energy or…