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Astronomers Watch Unfolding Saga of Massive Star Formation
Astronomers Unfolding Saga Massive Star
2015/4/13
A pair of images of a young star, made 18 years apart, has revealed a dramatic difference that is providing astronomers with a unique, "real-time" look at how massive stars develop in the earliest sta...
Astronomers Catch Multiple-Star System in First Stages of Formation（图）
Astronomers Multiple-Star System First Stages of Formation
2015/3/4
For the first time, astronomers have caught a multiple-star system in the beginning stages of its formation, and their direct observations of this process give strong support to one of several suggest...
Simulations of damped Ly alpha and Lyman limit absorbers in different cosmologies: Implications for structure formation at high redshift
formation large scale structure of the Universe
2014/12/26
We use hydrodynamic cosmological simulations to study damped Lyα (DLA) and Lyman limit (LL) absorption at redshifts z = 2-4 in five variants of the cold dark matter scenario: COBE-normalized (CCDM), c...
Star formation in bright-rimmed clouds. I. Millimeter and submillimeter molecular line surveys
pre-main sequence clouds
2014/12/26
We present the results of the first detailed millimeter and submillimeter molecular line survey of bright-rimmed clouds, observed at FCRAO in the CO (J = 1 → 0), C18O (J = 1 → 0), HCO+ (J = 1 → 0), H1...
Star formation in bright-rimmed clouds. I. Millimeter and submillimeter molecular line surveys
pre-main sequence clouds
2014/12/26
We present the results of the first detailed millimeter and submillimeter molecular line survey of bright-rimmed clouds, observed at FCRAO in the CO (J = 1 → 0), C18O (J = 1 → 0), HCO+ (J = 1 → 0), H1...
The halo occupation distribution (HOD) describes the bias between galaxies and dark matter by specifying (1) the probability P(N|M) that a halo of virial mass M contains N galaxies of a particular cla...
Galaxy cluster formation from the large-scale structure: a case study of the Abell 2125 complex at z=0.247
C153 SW cD
2014/12/24
The structure of the universe is believed to have formed by clustering hierarchically from small to large scales. Much of this evolution occurs very slowly but at a few special times more rapid, viole...
Radio and Far-Infrared Emission as Tracers of Star Formation and Active Galactic Nuclei in Nearby Cluster Galaxies
AWM7 A426
2014/12/24
We have studied the radio and far-infrared (FIR) emission from 114 galaxies in the seven nearest clusters (<100 Mpc) with prominent X-ray emission to investigate the impact of the cluster environment ...
Pre-heating by pre-virialization and its impact on galaxy formation
dark matter large-scale structure of the universe
2014/12/24
We use recent observations of the H i mass function to constrain galaxy formation. The data conflict with the standard model where most of the gas in a low-mass dark matter halo is assumed to settle i...
Using high-resolution cosmological simulations, we study hydrogen and helium gravitational cooling radiation from gas accretion by young galaxies. We focus on the He II cooling lines, which arise from...
The interplay between star formation and the nuclear environment of our Galaxy: deep X-ray observations of the Galactic centre Arches and Quintuplet clusters
n star formation the nuclear environment
2014/12/24
The Galactic centre (GC) provides a unique laboratory for a detailed examination of the interplay between massive star formation and the nuclear environment of our Galaxy. Here, we present a 100-ks Ch...
Star formation and feedback in smoothed particle hydrodynamic simulations - I. Isolated galaxies
star formation supernova feedback
2014/12/24
We present an analysis of star formation and feedback recipes appropriate for galactic smoothed particle hydrodynamics simulations. Using an isolated Milky Way-like galaxy, we constrain these recipes ...
Star formation in NGC 5194 (M51a). II. The spatially resolved star formation law
galaxies formation
2014/12/23
We have studied the relationship between the star formation rate (SFR), surface density, and gas surface density in the spiral galaxy M51a (NGC 5194), using multiwavelength data obtained as part of th...
With the goal of investigating the degree to which the MIR emission traces the SFR, we analyze Spitzer 8 and 24 μm data of star-forming regions in a sample of 33 nearby galaxies with available HST NIC...
I review measurements of star formation in nearby galaxies in the UV-to-FIR wavelength range, and discuss their impact on SFR determinations in intermediate and high redshift galaxy populations. Exist...