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ON THE FORMATION AND EVOLUTION OF EARLY-TYPE GALAXIES
early-type galaxies galaxy evolution high-redshift galaxies
2014/12/9
Galaxies in the local Universe are characterized by blue, star-forming disk galaxies, and red, massive early-type galaxies (ETGs) whose star-formation has been quenched early in the Universe's history...
Measures of Star Formation Rates within Galaxies: the Impact of Diffuse Stellar Populations
galaxies:ISM ISM:structure infrared:galaxies infrared:ISM H{\sc ii} regions
2014/12/9
Thanks to the {\it Spitzer Space Telescope}, the infrared (IR) emission have been better studied in the past decades, as well as its relations to star formation rates (SFR) and the calibrations of IR ...
Dusty Star Formation in Extreme Environments: Galaxies and Galaxy Clusters in the Distant Universe
high-redshift galaxy clusters infrared environment Herschel
2014/12/9
In this thesis, we present a comprehensive study of the dust-obscured star formation (SF) activity in galaxy clusters out to high redshift using infrared (IR) imaging. Using hundreds of galaxy cluster...
Formation and large-scale confinement of jets emitted by young stars finally elucidated
young stars plane scientists
2014/10/30
An international team of scientists has succeeded in explaining the formation and propagation over astronomical distances of jetsof matter emitted by young stars—one of the most fascinating mysteries ...
Some 30 years ago, astronomers found that regions of ionized gas around young high mass stars remain small (under a third of a light-year) for ten times longer than they should if they were to expand ...
ALMA discovers a formation site of a giant planetary system（图）
a giant planetary system ALMA
2014/3/17
A team of Japanese astronomers has obtained a firm evidence of formation of a giant planetary system around a young star by the observations with the Atacama Large Millimeter/submillimeter Array (ALMA...
A Relic Star Cluster in the Sextans Dwarf Spheroidal Galaxy - Implications for Early Star and Galaxy Formation
Relic Star Cluster the Sextans Dwarf Spheroidal Galaxy Implications Galaxy Formation
2012/2/23
We present tentative evidence for the existence of a dissolved star cluster in the Sextans dwarf spheroidal galaxy. In a sample of six stars, we identify three (possibly four) stars around [Fe/H] =-2....
Insights on the Formation, Evolution, and Activity of Massive Galaxies From Ultra-Compact and Disky Galaxies at z=2-3
Insights Formation Evolution Activity Massive Galaxies Disky Galaxies
2011/10/9
We present our results on the structure and activity of massive galaxies at z=1-3 using one of the largest (166 with M_star>=5e10 M_sun) and most diverse samples of massive galaxies derived from the G...
A Mid-Infrared Indicator for Total Infrared Luminosity and Star Formation Rate of Local and High-Redshift Galaxies
Indicator Total Infrared Luminosity High-Redshift Galaxies
2011/10/9
We present a new method to use 24 micron observations to estimate the total infrared luminosity, LIR, and the star formation rate of star-forming galaxies across the redshift range 0 < z < 3. This is ...
Enriched haloes at redshift $z=2$ with no star-formation: Implications for accretion and wind scenarios
galaxies:evolution galaxies:formation galaxies:high-redshifts galaxies
2011/10/13
In order to understand which process (e.g. galactic winds, cold accretion) is responsible for the cool (T~10^4 K) halo gas around galaxies, we embarked on a program to study the star-formation propert...
The Chemical Evolution of Narrow Emission Line Galaxies: the Key to their Formation Processes
galaxy: activity galaxy: formation galaxy: chemical evolution
2011/10/20
Using the largest sample of narrow emission line galaxies available so far, we show that their spectral characteristics are correlated with different physical parameters, like the chemical abundances,...
Elemental abundance differences in the 16 Cygni binary system: a signature of gas giant planet formation?
Elemental abundance differences signature planet formation
2011/10/20
The atmospheric parameters of the components of the 16Cygni binary system, in which the secondary has a gas giant planet detected, are measured accurately using high quality observational data. Abunda...
Collapse thresholds for the formation of CDM haloes in the ellipsoidal collapse model
cosmology: dark matter – methods: numerical
2011/10/20
In the excursion set approach to structure formation initially spherical regions of the linear density field collapse if the average density contrast within them exceeds some critical value, \delta_c....
Manganese evolution in Omega Centauri: a clue to the cluster formation mechanisms?
nuclear reactions nucleosynthesis abundances – galaxies: evolution – globular clusters: individual: ω Centauri
2011/10/18
We model the evolution of manganese relative to iron in the progenitor system of the globular cluster Omega Centauri by means of a self-consistent chemical evolution model. We use stellar yields that ...
Understanding Compact Object Formation and Natal Kicks. III. The case of Cygnus X-1
Understanding Compact Object Formation Natal Kicks Cygnus X-1
2011/10/20
In recent years, accurate observational constraints become available for an increasing number of Galactic X-ray binaries. Together with proper motion measurements, we could reconstruct the full evolut...