相关论文: The Dynamical Mass of the Coma Cluster from Deep L…
The galaxy total mass inside the effective radius encode important information on the dark matter and galaxy evolution model. Total "central" masses can be inferred via galaxy dynamics or with gravitational lensing, but these methods have…
Physics invites the idea that space contains energy whose gravitational effect approximates that of Einstein's cosmological constant, Lambda; nowadays the concept is termed dark energy or quintessence. Physics also suggests the dark energy…
Although the existence of a faint background of starlight in the core of the Coma cluster has been well established (1,2), its origin is uncertain. This vast sea of stars could have formed outside the galaxies, using gas left over from the…
We have obtained deep and wide field imaging of the Coma cluster of galaxies with the CFH12K camera at CFHT in the B, V, R and I filters. In this paper, we present the observations, data reduction, catalogs and first scientific results. We…
We determine the luminosity function (LF) of galaxies in the core of the Coma cluster for M_R<=-11.4 (assuming H_0=75 km/s/Mpc), a magnitude regime previously explored only in the Local Group. Objects are counted in a deep CCD image of Coma…
Galaxy clusters, the most massive, dark-matter-dominated, and most recently assembled structures in the Universe, are key tools for probing cosmology. However, uncertainties in scaling relations that connect cluster mass to observables like…
Detection and study of the intracluster light in rich clusters of galaxies has been a problem of long standing challenge and interest. Using the lowest surface brightness images of the Coma cluster of galaxies in the g and r bands, from the…
How is mass distributed in the Universe? How does it compare with the distribution of light and stars? We address these questions by examining the distribution of mass, determined from weak lensing observations, and starlight, around…
The hot big-bang cosmology provides a reliable accounting of the Universe from about $10^{-2}\sec$ after the bang until the present, as well as a robust framework for speculating back to times as early as $10^{-43}\sec$. Cosmology faces a…
In a previous work it was shown that by considering the quantum nature of the gravitational field mediator, it is possible to introduce the momentum energy of the graviton into the Einstein equations as an effective cosmological constant.…
We present a deep wide-field narrow-band imaging survey of the local rich and dynamically relaxed Coma cluster of galaxies, carried out with the Wide Field Camera at the Isaac Newton Telescope. The survey covers a region of about 2.5 sq.…
The recent observational evidence for the current cosmic acceleration have stimulated renewed interest in alternative cosmologies, such as scenarios with interaction in the dark sector (dark matter and dark energy). In general, such models…
We constrain the assembly history of galaxies in the projected central 0.5 Mpc of the Coma cluster by performing structural decomposition on 69 massive (M_star >= 10^9 M_sun) galaxies using high-resolution F814W images from the HST Treasury…
We present Submillimeter Array (SMA) observations of seven massive molecular clumps which are dark in the far-infrared for wavelengths up to 70 $\mu$m. Our 1.3 mm continuum images reveal 44 dense cores, with gas masses ranging from 1.4 to…
The dark energy-cold dark matter paradigm ($\Lambda$CDM) has gained widespread acceptance because it explains the pattern of anisotropies observed in the cosmic microwave background radiation, the observed distribution of large scale…
We suggest an alternative framework for interpreting the current state of the visible universe. Our approach is based on a dynamical ``Cosmological Constant'' and the starting point is that a decaying vacuum produces matter. As we point…
A precise determination of the local dark matter density and an accurate control over the corresponding uncertainties are of paramount importance for Dark Matter (DM) searches. Using very recent high-resolution numerical simulations of a…
In this work, we study the Coma cluster, one of the richest and most well-known systems at low redshifts, to explore the importance of low-flux objects in the identification of cluster substructures. In addition, we conduct a study of the…
The sum of cosmic neutrino masses can be measured cosmologically, as the sub-eV particles behave as `hot' dark matter whose main effect is to suppress the clustering of matter compared to a universe with the same amount of purely cold dark…
We report on SPT-CLJ2011-5228, a giant system of arcs created by a cluster at $z=1.06$. The arc system is notable for the presence of a bright central image. The source is a Lyman Break galaxy at $z_s=2.39$ and the mass enclosed within the…