相关论文: Evolutionary Synthesis Models for the Formation of…
The galaxy population in rich local galaxy clusters shows a ratio of one quarter elliptical galaxies, two quarters S0 galaxies, and one quarter spiral galaxies. Observations of clusters at redshift 0.5 show a perspicuously different ratio,…
We use new models of stellar population synthesis to estimate the fraction of stars formed during the last major bursts of star formation in E/S0 galaxies in low-redshift clusters ($z\simlt0.4$) from the spectral signatures of…
We combine morphological classifications from deep HST imaging of a sample of 3 clusters at z=0.31 and a further 9 clusters at z=0.37-0.56 with existing spectroscopic observations of their E and S0 populations, to study the relative…
Elliptical and S0 galaxies dominate the galaxy population in nearby rich clusters such as Coma. Studies of the evolution of the colors, M/L ratios, and line indices of early-type galaxies indicate that they have been a highly homogeneous,…
We test the hypothesis that S0 galaxies are the descendants of fading spirals whose star formation has been shut down, by using the properties of their globular cluster (GC) systems. We estimate the amount by which the GC specific frequency…
(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…
Recent observations have revealed that the time evolution of the S0 number fraction at intermediate and high redshifts (0.2<z<0.8) is more dramatic in groups of galaxies than in clusters. In order to understand the origin of S0s in groups,…
We test the theory that lenticular (S0) galaxies form from spirals whose star formation has been shut down. We use the globular cluster specific frequency S_N, defined as the number of globular clusters normalised by the galaxy luminosity…
We combine UV/Optical/near-IR/mid-IR data on a sample of ~240 S0 galaxies to examine various star formation related processes in them. We split the sample into bright and faint S0 galaxies based on their K band luminosity. Comparing the…
In this work, we investigate the reason behind the increased occurrence of S0 galaxies in high density environments. Our sample comprises of $\sim$ 2500 spiral and $\sim$ 2000 S0 galaxies spanning a wide range of environments. Dividing the…
A one-zone chemo-spectro-photometric model is used to investigate the time evolution of disk galaxies whose star formation is truncated, and to determine the dependence of this evolution on the previous star formation history and the…
Hubble Space Telescope observations of distant clusters have suggested a steep increase in the proportion of S0 galaxies between clusters at high redshifts and similar systems the present-day. It has been proposed that this increase results…
Galaxy clusters provide powerful laboratories for the study of galaxy evolution, particularly the origin of correlations of morphology and star formation rate (SFR) with density. We construct visible to MIR spectral energy distributions…
We address the current crucial issues on the formation and evolution of cluster galaxies: ie., connection between the Butcher-Oemler effect, assembly of cluster galaxies, truncation of star formation, and the origin of S0 galaxies. We…
The study of galaxy morphology is fundamental to understand the physical processes driving the structural evolution of galaxies. It has long been known that dense environments host high fractions of early-type galaxies and low fractions of…
Using multi-wavelength data, from UV-optical-near-mid IR, for $\sim$6000 galaxies in the local Universe, we study the dependence of star formation on the morphological T-types for massive galaxies ($\log M_*/M_\odot \geq 10$). We find that,…
The abundance of elliptical, S0 and spiral galaxies in clusters is presented as a function of redshift comparing the results of the HST distant cluster studies with new data at z~0.2 and with the standard local comparison samples. This…
The low redshift Universe (z<~0.5) is not a dull place. Processes leading to the suppression of star formation and morphological transformation are prevalent: this is particularly evident in the dramatic upturn in the fraction of S0-type…
The morphological types of galaxies in nine clusters in the redshift range 0.1<z<0.25 are derived from very good seeing images taken at the NOT and the La Silla Danish telescopes. With the purpose of investigating the evolution of the…
A survey of H alpha emission in 320 spiral galaxies in 8 nearby clusters shows an enhancement of circumnuclear starburst emission with increasingly rich clusters. These observations provide convincing evidence that spirals have been…