搜索结果: 1-15 共查到“等离子体天体物理学 Galaxy”相关记录20条 . 查询时间(0.068 秒)
Extrapolating the Evolution of Galaxy Sizes to the Epoch of Reionization
galaxies evolution formation high-redshift cosmology theory
2010/11/16
We use data on the high-redshift evolution of the size distribution and luminosity function of galaxies to constrain the relationship between their star formation eciency and starburst lifetime. Base...
The Birth of a Galaxy: Primordial Metal Enrichment and Population II Stellar Populations
cosmology methods numerical hydrodynamics radiative transfer star formation
2010/11/15
Population III stars first form in dark matter halos with masses around 106M⊙. By definition,
they are metal-free, and their protostellar collapse is driven by molecular hydrogen cooling in the gas-p...
Constraining the ages of the fireballs in the wake of the dIrr galaxy VCC1217 / IC3418
Galaxies clusters individual: Virgo Galaxies evolution Galaxies irregular
2010/11/11
Context. A complex of Hα emitting blobs with strong FUV excess is associated to the dIrr galaxy VCC1217 / IC3418 (Hester et al.2010), and extends up to 17 Kpc in the South-East direction. These outsta...
This paper presents the rst results from a new citizen science project: Galaxy Zoo Supernovae. This proof of concept project uses members of the public to identify su-pernova candidates from the late...
Evidence of major dry mergers at M* > 2 x 10^11 Msun from curvature in early-type galaxy scaling relations?
galaxies formation
2010/11/11
For early-type galaxies, the correlations between stellar mass and size, velocity dis-
persion, surface brightness, color, axis ratio and color-gradient all indicate that two mass scales, M∗ = ...
Galaxy clustering and projected density profiles as traced by satellites in photometric surveys: Methodology and luminosity dependence
Galaxy clustering projected density profiles photometric surveys
2010/11/12
We develop a new method which measures the projected density distribution wp(rp)n of photometric galaxies surrounding a set of spectroscopically-identified galaxies, and simultaneously the projected c...
Calibrating Galaxy Redshifts Using Absorption by the Surrounding Intergalactic Medium
galaxies high-redshift intergalactic medium quasars absorption lines
2010/11/11
Rest-frame UV spectral lines of star-forming galaxies are systematically offset fromthe galaxies’systemic redshifts, probably because of large-scale outflows.We calibrate galaxy redshifts measured fro...
A2163: Merger events in the hottest Abell galaxy cluster II. Subcluster accretion with galaxy-gas separation
Galaxies clusters general – Galaxies intergalactic medium – X-rays galaxies clusters
2010/11/16
Located at z = 0.203, A2163 is a rich galaxy cluster with an intra-cluster medium (ICM) that exhibits extraordinary properties,including an exceptionally high X-ray luminosity, average temperature, an...
A radio minihalo in the extreme cool-core galaxy cluster RXCJ1504.1-0248
radiation mechanism non-thermal – galaxies clusters general – galaxies
2010/11/16
Aims. We report the discovery of a radio minihalo in RXCJ1504.1-0248, a massive galaxy cluster that has an extremely luminous cool core. To date, only 9 radio minihalos are known, thus the discovery o...
Particle reacceleration by compressible turbulence in galaxy clusters: effects of reduced mean free path
acceleration of particles - turbulence - radiation mechanisms non{thermal - galaxies clusters general radio continuum general - X{rays general
2010/11/11
Direct evidence for in situ particle acceleration mechanisms in the inter-galactic-medium (IGM) is provided by the di use Mpc{scale synchrotron emissions observed from galaxy clusters.
Over the past years observations of young and populous star clusters have shown that the stellar initial mass function (IMF) can be conveniently described by a two-part power-law with an exponent 2 =...
Particle Acceleration on Megaparsec Scales in a Merging Galaxy Cluster
Particle Acceleration Megaparsec Scales Merging Galaxy Cluster
2011/1/10
Galaxy clusters form through a sequence of mergers of smaller galaxy clusters and groups. Models of diffusive shock acceleration (DSA) suggest that in shocks that occur during cluster mergers, particl...
We present a brief history of Galactic astrophysics, and explain the origin of halo substructure in the Galaxy. We motivate our study of tidal streams by highlighting the tight constraints that analys...
The impact of numerical viscosity in SPH simulations of galaxy clusters
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2011/1/6
A SPH code employing a time-dependent artificial viscosity scheme is used to construct a large set of N-body/SPH cluster simulations for studying the impact of artificial viscosity on the thermodynami...
The Properties of X-ray Cold Fronts in a Statistical Sample of Simulated Galaxy Clusters
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2011/1/6
We examine the incidence of cold fronts in a large sample of galaxy clusters extracted from a (512h^-1 Mpc) hydrodynamic/N-body cosmological simulation with adiabatic gas physics computed with the Enz...