搜索结果: 1-15 共查到“天文学 halos”相关记录34条 . 查询时间(0.04 秒)
Milky Way-like Galaxies in Early Universe Embedded in 'Super Halos'
Milky Way-like Galaxies Early Universe Embedded Super Halos
2017/3/30
By harnessing the extreme sensitivity of the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers have directly observed a pair of Milky Way-like galaxies seen when the universe was only e...
A study of spiral galaxies seen edge-on has revealed that "halos" of cosmic rays and magnetic fields above and below the galaxies' disks are much more common than previously thought.An international t...
Investigating the long-term evolution of galaxies: Noise, cuspy halos and bars
cuspy halos bars
2014/12/26
I review the arguments for the importance of halo structure in driving galaxy evolution and coupling a galaxy to its environment. We begin with a general discussion of the key dynamics and examples of...
We have used the Far Ultraviolet Spectroscopic Explorer to search for O VI λλ1031.926, 1037.617 emission in the halos of the edge-on spiral galaxies NGC 4631 and NGC 891. In NGC 4631, we detected O VI...
I review studies of the hot gaseous medium in and around nearby normal disk galaxies, including the Milky Way. This medium represents a reservoir of materials required for lasting star formation, a de...
A GREEN BANK TELESCOPE SURVEY FOR H I 21 cm ABSORPTION IN THE DISKS AND HALOS OF LOW-REDSHIFT GALAXIES
21 cm absorption survey Green Bank Telescope
2014/12/20
We present an H I 21 cm absorption survey with the Green Bank Telescope (GBT) of galaxy-quasar pairs selected by combining galaxy data from the Sloan Digital Sky Survey (SDSS) and radio sources from t...
Dark Matter Halos: Assembly, Clustering and Sub-halo Accretion
Dark matter Galaxy formation Halos
2014/12/9
I carried out systematic studies on the assembly history of dark matter halos, using numerical simulations and semi-analytical methods. First, I look into dark halo mass assembly history. I confirmed ...
High-resolution Ultraviolet Spectroscopy of Gas in Galaxy Halos and Large-scale Structures
galaxy intergalactic medium
2014/12/9
This dissertation presents spectroscopic studies of gas in galaxy halos and large-scale structures through high-resolution quasar absorption lines. The broad goal of this effort is to learn how galaxi...
Radio continuum observations of new radio halos and relics from the NVSS and WENSS surveys
Radio Continuum: galaxies – Galaxies: Clusters: general, intracluster medium – Cosmology: large-scale structure of Universe
2011/10/20
Radio halos and relics are diffuse radio sources found in galaxy clusters showing significant substructure at X-ray wavelengths. These sources provide important information about non-thermal processes...
Pairwise Velocities of Dark Matter Halos: a Test for the Lambda Cold Dark Matter Model using the Bullet Cluster
method : N-body simulations — galaxies : evolution — galaxies : for-mation — galaxies: clusters — cosmology : theory — cosmology : dark matter
2011/10/13
The existence of a bullet cluster (such as 1E0657-56) poses a challenge to the concordance Lambda cold dark matter model. Here we investigate the velocity distribution of dark matter halo pairs in lar...
Interaction between dark matter sub-halos & galactic gaseous disk
Interaction sub-halos galactic gaseous disk
2011/10/8
We investigate the idea that the interaction of Dark Matter (DM) sub-halos with the gaseous disk of galaxies can be the origin for the observed holes and shells found in their neutral hydrogen (HI) di...
Statistical mechanics of collisionless orbits. I. Origin of central cusps in dark-matter halos
Cosmology and Extragalactic Astrophysics (astro-ph.CO) Statistical Mechanics (cond-mat.stat-mech)
2010/12/23
We present an equilibrium statistical mechanical theory of collisionless self-gravitational systems with isotropic velocity distributions.
Evidence Against Dark Matter Halos Surrounding the Globular Clusters MGC1 and NGC 2419
Dark Matter Halos Surrounding the Globular Clusters MGC1 NGC 2419
2011/1/11
The conjecture that the ancient globular clusters (GCs) formed at the center of their own dark matter halos was first proposed by Peebles (1984), and has recently been revived to explain the puzzling ...
Common origin for radio relics and halos: galaxy cluster-wide, homogeneous cosmic-ray distribution, and evolving magnetic fields
galaxies clusters general — galaxies clusters intracluster medium —X-rays galaxies: clusters
2010/11/10
Some galaxy clusters show diffuse radio emission in the form of peripheral relics (so
far attributed to primary, shock-(re)accelerated electrons) or central halos. Analysing
radio and X-ray data fro...
Radio Halos and the importance of future observations at low frequency
Radio Halos future observations low frequency
2010/11/11
Radio observations discovered large scale non thermal sources in the central Mpc regions of
dynamically disturbed galaxy clusters (radio halos). The morphological and spectral properties of these sou...