Results 51 to 60 of about 593,443 (246)
It is argued that within the standard Big Bang cosmological model the bulk of the mass of the luminous parts of the large galaxies likely had been assembled by redshift z ∼ 10. Galaxy assembly this early would be difficult to fit in the widely discussed adiabatic cold dark matter model for structure formation ...
openaire +2 more sources
Light Elements in the Universe
Due to their production sites, as well as to how they are processed and destroyed in stars, the light elements are excellent tools to investigate a number of crucial issues in modern astrophysics: from stellar structure and non-standard processes at work
Sofia Randich, Laura Magrini
doaj +1 more source
Anisotropic Galaxy-Galaxy Lensing
We investigate the weak lensing shear due to dark matter galaxy halos whose mass distributions, as projected on the sky, are nearly elliptical. The shear pattern due to these halos is anisotropic about the lens centers and we quantify the level of anisotropy by comparing the mean shear experienced by sources located closest to the major axes of the ...
Brainerd, T. G., Wright, C. O.
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A growing number of low luminosity and low surface brightness astronomical objects challenge traditional notions of both galaxies and star clusters. To address this, we propose a definition of galaxy independent of the cold dark matter model of the universe: A galaxy is a gravitationally bound set of stars whose properties cannot be explained by a ...
Willman, Beth, Strader, Jay
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Joint galaxy–galaxy lensing and clustering constraints on galaxy formation [PDF]
ABSTRACT We compare predictions for galaxy–galaxy lensing profiles and clustering from the Henriques et al. public version of the Munich semi-analytical model (SAM) of galaxy formation and the IllustrisTNG suite, primarily TNG300, with observations from KiDS + GAMA and SDSS-DR7 using four different selection functions for the lenses ...
Malin Renneby +7 more
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We study the host galaxy properties of the tidal disruption object, Swift J164449.3+573451 using long-term optical to near-infrared (NIR) data. First, we decompose the galaxy surface brightness distribution and analyze the morphology of the host galaxy ...
Choi, Philip +8 more
core +1 more source
Metric completions, the Heine-Borel property, and approachability
We show that the metric universal cover of a plane with a puncture yields an example of a nonstandard hull properly containing the metric completion of a metric space.
Kanovei Vladimir +2 more
doaj +1 more source
Constraints on Assembly Bias from Galaxy Clustering
We constrain the newly-introduced decorated Halo Occupation Distribution (HOD) model using SDSS DR7 measurements of projected galaxy clustering or r-band luminosity threshold samples.
Bosch, Frank C. van den +4 more
core +1 more source
Quasar-galaxy and AGN-galaxy cross-correlations [PDF]
We compute quasar-galaxy and AGN-galaxy cross-correlation functions for samples taken from the \cite{VCV98} catalog of quasars and active galaxies, using tracer galaxies taken from the Edinburgh/Durham Southern Catalog.
Babul A. +9 more
core +3 more sources
Towards an understanding of third-order galaxy-galaxy lensing
Third-order galaxy-galaxy lensing (G3L) is a next generation galaxy-galaxy lensing technique that either measures the excess shear about lens pairs or the excess shear-shear correlations about lenses.
Bartelmann +31 more
core +1 more source

