搜索结果: 1-15 共查到“星系与宇宙学 medium”相关记录16条 . 查询时间(0.096 秒)
Metal enrichment of the intergalactic medium at z=3 by galactic winds
galactic winds intergalactic medium
2014/12/26
Studies of quasar absorption lines reveal that the low-density intergalactic medium (IGM) at z ~ 3 is enriched to between 10-3 and 10-2 solar metallicity. This enrichment may have occurred in an early...
Metal enrichment of the intergalactic medium in cosmological simulations
intergalactic medium formation starburst
2014/12/26
Observations have established that the diffuse intergalactic medium (IGM) at z ~ 3 is enriched to ~10-2.5 solar metallicity and that the hot gas in large clusters of galaxies (ICM) is enriched to - Z ...
Enrichment of the intergalactic medium by radiation pressure-driven dust efflux
intergalactic medium abundances
2014/12/26
The presence of metals in hot cluster gas and in Lyα absorbers, as well as the mass-metallicity relation of observed galaxies, suggest that galaxies lose a significant fraction of their metals to the ...
X-ray absorption by the low-redshift intergalactic medium: A numerical study of the Lambda cold dark matter model
theory intergalactic medium
2014/12/24
Using a hydrodynamic simulation of a cold dark matter universe with a cosmological constant, we investigate the "X-ray forest" absorption imprinted on the spectra of background quasars by the interven...
X-Ray Absorption Line Spectroscopy of the Galactic Hot Interstellar Medium
Cyg X–2 V801 Ara
2014/12/24
We present an X-ray absorption line spectroscopic study of the large-scale hot interstellar medium (HISM) in the Galaxy. We detect Ne IX Kα absorption lines in the Chandra grating spectra of seven Gal...
Probing the Local Group Medium toward Markarian 421 with Chandra and the Far Ultraviolet Spectroscopic Explorer
halo intergalactic medium
2014/12/24
We report the detection of highly ionized gas at z ~ 0 seen in resonant UV and X-ray absorption lines toward the z = 0.03 blazar Mrk 421. A total of 13 X-ray and three UV lines were measured (or upper...
X-Ray Absorption Spectroscopy of the Multiphase Interstellar Medium: Oxygen and Neon Abundances
ISM 4U 1820–303
2014/12/24
X-ray absorption spectroscopy provides a powerful tool in determining the metal abundances in various phases of the interstellar medium (ISM). We present a case study of the sight line toward 4U 1820-...
Chandra Detection of Fe XVII in Absorption: Iron Abundance in the Hot Gaseous Interstellar Medium
4U 1820–303 abundances
2014/12/24
The iron depletion level and the gas-phase iron abundance in the hot (~106 K) interstellar medium (ISM) are critical to our understanding of its energy balance as well as the thermal sputtering, cooli...
The intergalactic medium over the last 10 billion years I: Lyman alpha absorption and physical conditions
intergalactic medium hydrodynamic
2014/12/20
The intergalactic medium (IGM) is the dominant reservoir of baryons at all cosmic epochs. We investigate the evolution of the IGM from z=2-0 in 48 Mpc/h, 110-million particle cosmological hydrodynamic...
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...
Turbulence in the interstellar medium
Many variables Spectral imaging Observation The interstellar medium. The star gas
2014/12/9
The multivariate technique of principal component analysis (PCA) is a powerful statistical tool with which to describe spectral line imaging observations of the molecular interstellar medium. In parti...
The intergalactic medium unveiled: Caltech's Cosmic Web Imager
The intergalactic medium unveiled Caltech's Cosmic Web Imager
2014/5/13
Caltech astronomers have taken unprecedented images of the intergalactic medium (IGM)—the diffuse gas that connects galaxies throughout the universe—with the Cosmic Web Imager, an instrument designed ...
The effect of feedback on the emission properties of the Warm-Hot Intergalactic Medium
feedback emission properties the Warm-Hot Intergalactic Medium
2012/2/21
At present, 30-40 per cent of the baryons in the local Universe is still undetected. According to theoretical predictions, this gas should reside in filaments filling the large-scale structure (LSS) i...
Faint Extended OH Emission from the Local Interstellar Medium in the Direction l \approx 108\circ, b \approx 5\circ
OH Emission Local Interstellar Medium Cosmology and Extragalactic Astrophysics
2012/2/21
We have mapped faint 1667 OH line emission (TA \approx 20 - 40 mK in our \approx 30' beam) along many lines of sight in the Galaxy covering an area of \approx 4\circ \times 4\circ in the general direc...
Determination of the Mean HI Absorption of the Intergalactic Medium
Quasar absorption lines—galaxies intergalactic medium
2010/9/15
In recent years, the Lyman-α forest in quasar spectra has been used, together with N-body simulations, to determine the underlying matter distribution in the intergalactic medium (IGM). One of the key...