搜索结果: 1-15 共查到“天文学 GROUPS”相关记录33条 . 查询时间(0.093 秒)
X-ray scaling relations of galaxy groups in a hydrodynamic cosmological simulation
theory clusters
2014/12/26
We examine the scalings of X-ray luminosity, temperature, and dark matter or galaxy velocity dispersion for galaxy groups in a ΛCDM cosmological simulation, which incorporates gravity, gas dynamics, r...
The Evolution of Galaxy Disks in Dense Environments - Lessons from Compact Galaxy Groups
evolution interactions
2014/12/23
Disk galaxies in compact galaxy groups exhibit a remarkable shortfall of neutral hydrogen compared to both isolated spirals and spirals in more loose groups, but the origin of this HI deficiency remai...
Galaxy evolution in Hickson compact groups: the role of ram-pressure stripping and strangulation
evolution interactions
2014/12/23
Galaxies in compact groups tend to be deficient in neutral hydrogen compared to isolated galaxies of similar optical properties. In order to investigate the role played by a hot intragroup medium (IGM...
Ongoing assembly of massive galaxies by major merging in large groups and clusters from the SDSS
general surveys
2014/12/23
We investigate the incidence of major mergers creating massive (Mstar > 1011 M⊙) galaxies in present-day (z≤ 0.12) groups and clusters. Using a volume-limited sample of 845 groups with dark matter hal...
Structural properties of central galaxies in groups and clusters
fundamental parameters structure.
2014/12/22
Using a statistically representative sample of 911 central galaxies (CENs) from the Sloan Digital Sky Survey (SDSS) Data Release 4 group catalogue, we study how the structure (shape and size) of the f...
DETECTION OF DIFFUSE NEUTRAL INTRAGROUP MEDIUM IN HICKSON COMPACT GROUPS
new Green Bank Telescope gas mass fraction
2014/12/20
We present new Green Bank Telescope (GBT) 21 cm neutral hydrogen (H I) observations of a complete distance-limited sample of 22 Hickson Compact Groups (HCGs) with at least four true members. We detect...
Multiwavelength Study Of The Distribution Of Neutral Gas In And Around Galaxies And Groups Of Galaxies
Pure sciences Absorption Compact groups Galaxy evolution Hydrogen Lyman alpha
2014/12/9
We study the distribution and nature of neutral hydrogen in various environments. We start by exploring the disk and halos of galaxies in Chapter 1. Our sample consists of 23 sightlines through 15 low...
The luminosities of the brightest cluster galaxies and brightest satellites in SDSS groups
galaxies: luminosity function
2011/10/11
We show that the distribution of luminosities of Brightest Cluster Galaxies, in two SDSS-based group catalogs, suggests that BCG luminosities are just the statistical extremes of the group galaxy lumi...
Young stellar groups in M 33 galaxy: delineation and main parameters
Young stellar groups in M 33 galaxy: delineation and main parameters
2011/10/18
The problem of (non-)existence of a typical size of the stellar associations is revisited by use of deep UBVRI stellar CCD photometry in M 33 from the Local Group Survey (Massey et al. 2006). We compa...
Galaxy evolution in groups and clusters: star formation rates, red sequence fractions, and the persistent bimodality
methods: statistical-galaxies: groups: general-galaxies: clusters:general-galaxies: haloes-galaxies: evolution-galaxies: star formation
2011/10/17
Using galaxy group/cluster catalogs created from the Sloan Digital Sky Survey Data Release 7, we examine in detail the specific star formation rate (SSFR) distribution of satellite galaxies and its de...
Two fossil groups of galaxies at z~0.4 in the COSMOS: accelerated stellar-mass build-up, different progenitors
X-rays: galaxies: clusters – galaxies: groups: general – galaxies: evolution – galaxies: luminosity function, mass function
2011/10/12
We report on 2 fossil groups of galaxies at z=0.425 and 0.372 discovered in the Cosmic Evolution Survey (COSMOS) area. Selected as X-ray extended sources, they have total masses (M_200) of 1.9(+/-0.41...
A mid-IR study of Hickson Compact Groups II. Multi-wavelength analysis of the complete GALEX-Spitzer Sample
Infrared: galaxies —Galaxies: evolution— Galaxies: interactions —Galaxies: star formation
2011/10/10
We present a comprehensive study on the impact of the environment of compact galaxy groups on the evolution of their members using a multi-wavelength analysis, from the UV to the infrared, for a sampl...
The Star Cluster Populations of Compact Galaxy Groups
Cluster Populations Compact Galaxy Groups
2011/10/11
Star clusters are ideal tracers of star formation activity in systems outside the volume that can be studied using individual, resolved stars. These unresolved clusters span orders of magnitude in bri...
We present photometric and spectroscopic observations of the members of three previously cataloged compact group (CG) candidates at redshifts z>0.3. These confirm spectroscopic redshifts compatible wi...
Intergalactic Gas in Groups of Galaxies: Implications for Dwarf Spheroidal Formation and The Missing Baryons Problem
Implications Spheroidal Formation Missing Baryons
2011/9/28
Radio galaxies with bent jets are predominantly located in groups and clusters of galaxies. We use bent-double radio sources, under the assumption that their jets are bent by ram-pressure, to probe in...