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The Turbulence Spectrum of Molecular Clouds in the Galactic Ring Survey: A Density-Dependent PCA Calibration
Turbulence Spectrum Molecular Clouds Galactic Ring Survey
2011/10/13
Turbulence plays a major role in the formation and evolution of molecular clouds. The problem is that turbulent velocities are convolved with the density of an observed region. To correct for this con...
An HI column density threshold for cold gas formation in the Galaxy
column density threshold cold gas formation Galaxy
2011/9/28
We report the discovery of a threshold in the HI column density of Galactic gas clouds below which the formation of the cold phase of HI is inhibited. This threshold is at $N_{HI} = 2 \times 10^{20}$ ...
A modified star formation law as a solution to open problems in galaxy evolution
galaxies: evolution – galaxies: formation – galaxies: stellar content –galaxies: haloes
2011/10/13
In order to reproduce the low mass end of the stellar mass function, most current models of galaxy evolution invoke very efficient supernova feedback. This solution seems to suffer from several shortc...
Genesis of the dusty Universe: modeling submillimetre source counts
galaxies: evolution – galaxies: general – galaxies: starburst – infrared:galaxies – submillimetre: galaxies
2011/10/13
We model the evolution of IR galaxies using a phenomenological approach to match the observed source counts at different IR wavelengths. We introduce a new algorithm for reproducing source counts base...
Convergence of Galaxy Properties with Merger Tree Temporal Resolution
galaxies cosmology galactic structure galaxy evolution galaxy formation
2011/10/12
Dark matter halo merger trees are now routinely extracted from cosmological simulations of structure formation. These trees are frequently used as inputs to semi-analytic models of galaxy formation to...
Is light neutralino as dark matter still viable?
Galaxies: clusters: general intracluster medium Radio continuum: galaxies Radio telescopes
2011/9/29
Motivated by the recent re-confirmation by CoGENT of the low-energy excess of events observed last year, and the recent improved limits from the XENON-100 experiment that are in contention with the Co...
Can Self Organized Critical Accretion Disks Generate a Log-normal Emission Variability in AGN?
Accretion accretion disks
2011/9/29
Active Galactic Nuclei (AGN), such as Seyfert galaxies, quasars, etc., show light variations in all wavelength bands, with various amplitude and in many time scales. The variations usually look errati...
Theoretical Spectra of the Am CVn Binary System SDSS J0926+3624 : Effects of Irradiation onto the Donor Stars
Theoretical Spectra Binary System Effects Irradiation Donor Stars
2011/9/29
Taking into account a range of parameters determined from the evolutionary models and available observational data, the detailed non-LTE spectra for the primary star and the irradiated donor star in t...
Sparse aperture masking at the VLT I. Faint companion detection limits for the two debris disk stars HD 92945 and HD 141569
Instrumentation: high angular resolution – Stars: planetary systems – Stars: individual
2011/9/29
Observational data on companion statistics around young stellar systems is needed to flesh out the formation pathways for extrasolar planets and brown dwarfs. Aperture masking is a new technique that ...
Observations of the most distant bright quasars imply that billion solar mass supermassive black holes (SMBH) have to be assembled within the first eight hundred million years. Under our standard gala...
Redshift Evolution of the Galaxy Velocity Dispersion Function
Redshift Evolution Galaxy Velocity Dispersion
2011/9/28
We present a study of the evolution of the galaxy Velocity Dispersion Function (VDF) from z=0 to z=1.5 using photometric data from the UKIDSS Ultra Deep Survey (UDS) and Newfirm Medium Band Survey (NM...
Multiwavelength campaign on Mrk 509. I. Variability and spectral energy distribution
Galaxies: active – quasars: absorption lines – X-rays: general
2011/9/27
(Abridged) Active galactic nuclei show a wealth of interesting physical processes, some of which are poorly understood. We want to address a number of open questions, including the location and physic...
Nature, formation and evolution of High Mass X-ray Binaries
Nature formation evolution Mass X-ray Binaries
2011/9/27
The aim of this review is to describe the nature, formation and evolution of the three kinds of high mass X-ray binary (HMXB) population: i. systems hosting Be stars (BeHMXBs), ii. systems accreting t...
Confronting 2D delayed-detonation models with light curves and spectra of Type Ia supernovae
supernovae: general
2011/9/26
We compare models for Type Ia supernova (SN Ia) light curves and spectra with an extensive set of observations. The models come from a recent survey of 44 two-dimensional delayed-detonation models com...
The Lambda Orionis Star Forming Region：the Spitzer perspective
Spitzer perspective Lambda Orionis Star Forming Region
2009/6/30
The Lambda Orionis Star Forming Region：the Spitzer perspective。