搜索结果: 1-15 共查到“天文学 Gradients”相关记录19条 . 查询时间(0.203 秒)
Star formation in self-gravitating disks in active galactic nuclei. I. Metallicity gradients in broad line regions
Star formation self-gravitating disks active galactic Metallicity gradients
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2011/10/11
It has been suggested that the high metallicity generally observed in active galactic nuclei (AGNs) and quasars originates from ongoing star formation in the self-gravitating part of accretion disks a...
Stellar mass-to-light ratio gradients in galaxies: correlations with mass
dark matter – galaxies : evolution – galaxies : galaxies : general –galaxies : elliptical and lenticular, cD.
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2011/10/9
We analyze the stellar mass-to-light ratio (M/L) gradients in a large sample of local galaxies taken from the Sloan Digital Sky Survey, spanning a wide range of stellar masses and morphological types....
AGN Unification at z ~ 1: u - R Colors and Gradients in X-ray AGN Hosts
Unification Colors Gradients Hosts
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2011/10/8
We present uncontaminated rest-frame u - R colors of 78 X-ray-selected AGN hosts at 0.5 < z < 1.5 in the Chandra Deep Fields measured with HST/ACS/NICMOS and VLT/ISAAC imaging. We also present spatial...
Evolution of the Solar Nebula. IX. Gradients in the Spatial Heterogeneity of the Short-Lived Radioisotopes $^{60}$Fe and $^{26}$Al and the Stable Oxygen Isotopes
Evolution Solar Nebula IX. Gradients Spatial Heterogeneity Short-Lived Stable Oxygen Isotopes
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2011/9/27
Short-lived radioisotopes (SLRI) such as $^{60}$Fe and $^{26}$Al were likely injected into the solar nebula in a spatially and temporally heterogeneous manner. Marginally gravitationally unstable (MGU...
Spectroscopic observations of a sample of dwarf spiral galaxies. II- Abundance gradients
dwarf spiral galaxies Abundance gradients
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2010/11/10
The oxygen gradient of four dS galaxies has been determined using abundances for several
Hii regions determined with four different methods. The gradient slopes of the three non-barred
galaxies in t...
Colour gradients in normal and compact early-type galaxies at 1
galaxies elliptical and lenticular CD galaxies formation galaxies: evolution
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2010/11/15
We have derived colour gradients for a sample of 20 early-type galaxies (ETGs) at 1 < z
spec < 2 selected from the GOODS-South field. The sample includes both nor-mal ETGs (13) having effective radii...
Gas accretion as the origin of chemical abundance gradients in distant galaxies
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
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2010/12/29
It has recently been suggested that galaxies in the early Universe can grow through the accretion of cold gas, and that this may have been the main driver of star formation and stellar mass growth.
Colour and stellar population gradients in galaxies
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
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2010/12/24
We discuss the colour, age and metallicity gradients in a wide sample of local SDSS early- and late-type galaxies. From the fitting of stellar population models we find that metallicity is the main dr...
The effect of pressure gradients on luminosity distance - redshift relations
pressure gradients luminosity distance redshift relations
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2010/3/18
Inhomogeneous cosmological models have had significant success in explaining cosmological observations without the need for dark energy. Generally, these models imply inhomogeneous matter distribution...
A 1.4 GHZ and 14.7 GHZ analysis of density gradients in galactic planetary nebulae
A 1.4 GHZ 14.7 GHZ density gradients galactic planetary nebulae
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2009/7/9
A 1.4 GHZ and 14.7 GHZ analysis of density gradients in galactic planetary nebulae。
Carbon and oxygen galactic gradients
Carbon oxygen galactic gradients
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2009/6/25
Carbon and oxygen galactic gradients。
Radial abundance gradients as observational constraints of galactic evolution：
planetary nebulae galactic evolution
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2009/6/25
Radial abundance gradients as observational constraints of galactic evolution：
planetary nebulae and other objects。
Temperature and Density Gradients in the Orion Nebula
Temperature Density Gradients Orion Nebula
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2009/6/15
Temperature and Density Gradients in the Orion Nebula。
Density gradients and internal dust in the Orion nebula
Density gradients internal dust Orion nebula
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2009/6/11
Density gradients and internal dust in the Orion nebula。
Radial gradients and metallicities in the galactic disk
Radial gradients metallicities galactic disk
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2009/6/11
Radial gradients and metallicities in the galactic disk。