相关论文: Optically-passive spirals: The missing link in gra…
Quenched massive spiral galaxies have attracted great attention recently, as more data is available to constrain their environment and cold gas content. However, the quenching mechanism is still uncertain, as it depends on the mass range…
The clustering of galaxies relative to the mass distribution declines with time because: first, nonlinear peaks become less rare events; second, the densest regions stop forming new galaxies because gas there becomes too hot to cool and…
We examine the origin of clustercentric gradients in the star formation rates and colors of rich cluster galaxies within the context of a simple model where clusters are built through the ongoing accretion of field galaxies. The model…
Clusters of galaxies at z>1 are expected to be increasingly active sites of star formation. To test this, an 850um survey was undertaken of eight high-redshift clusters at z=1.6-2.0 using SCUBA-2 on the James Clerk Maxwell Telescope.…
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…
The dense molecular cloud cores that form stars, like other self-gravitating objects, undergo bulk oscillations. Just at the point of gravitational instability, their fundamental oscillation mode has zero frequency. We study, using…
The evolution of low-mass galaxies is shaped by both internal processes and environmental factors, yet the role of environment and mergers in regulating their growth and star formation rates remains poorly understood, especially in the…
The early universe hosted a large population of low-mass virialized "minihalos," that were not massive enough to form stars on their own. While most minihalos were photoevaporated by ionizing photons from star-forming galaxies, these…
Obscured or narrow-line active galaxies offer an unobstructed view of the quasar environment in the presence of a luminous and vigorously accreting black hole. We exploit the large new sample of optically selected luminous narrow-line…
(Abridged) We have used optical spectroscopy to investigate the radio- selected active galaxy populations in a sample of 20 nearby Abell clusters. The spectra were used to characterize the galaxies as AGN or galaxies forming stars at rates…
Massive galaxies are thought to form in two phases: an initial, early collapse of gas and giant burst of central star formation, followed by the later accretion of material that builds up their stellar and dark matter haloes. The globular…
Promising methods for studying galaxy evolution rely on optical emission line width measurements to compare intermediate-redshift objects to galaxies with equivalent masses at the present epoch. However, emission lines can be misleading. We…
In this paper, we try to understand why the classical bulge fraction observed in S0 galaxies is significantly higher than that in spiral galaxies. We carry out a comparative study of the bulge and global properties of a sample of spiral and…
Star-forming galaxies can in principle be transformed into passive systems by a multitude of processes that quench star formation, such as the halting of gas accretion (starvation) or the rapid removal of gas in AGN-driven outflows.…
A recent observational result finds that the quenching of satellites in groups at $z=0.08$ has an angular dependence relative to the semi-major axis of the central galaxy. This observation is described as `anisotropic quenching' or `angular…
Planet formation is accompanied by the formation of comet clouds. In systems where planets migrate on rapid timescales, the diffusive evolution of comet orbits may stall, resulting in a comet cloud intermediate between a flattened Kuiper…
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,…
(Abridged) We present new optical and near-infrared imaging for a sample of 98 spectroscopically-selected galaxy groups at 0.25<z<0.55. We measure accurate colours for group members and the surrounding field population, statistically…
Using the CLASH-VLT survey, we assembled an unprecedented sample of 1234 spectroscopically confirmed members in Abell~S1063, finding a dynamically complex structure at z_cl=0.3457 with a velocity dispersion \sigma_v=1380 -32 +26 km s^-1. We…
We present clustering measurements and halo masses of star forming galaxies at 0.2 < z < 1.0. After excluding AGN, we construct a sample of 22553 24 {\mu}m sources selected from 8.42 deg^2 of the Spitzer MIPS AGN and Galaxy Evolution Survey…