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A close halo of large transparent grains around extreme red giant stars
Spatially resolved, multiwavelength observations of circumstellar dust shells of three stars on the asymptotic giant branch of the Hertzsprung–Russell diagram show that transparency usually implies insufficient radiative pressure to drive a wind, the radiation field can accelerate these large grains through photon scattering rather than absorption—a plausible mass loss mechanism for lower-amplitude pulsating stars.
An Empirical formula for the mass-loss rates of dust-enshrouded red supergiants and oxygen-rich asymptotic giant branch stars
We present an empirical determination of the mass-loss rate as a function of stellar luminosity and effective tem- perature, for oxygen-rich dust-enshrouded Asymptotic Giant Branch stars and red
Fundamental parameters and infrared excesses of Hipparcos stars
We derive the fundamental parameters (temperature and luminosity) of 107 619 Hipparcos stars and place these stars on a true Hertzsprung–Russell diagram. This is achieved by comparing bt-settl model
Massive-Star Supernovae as Major Dust Factories
Observations of the Type II supernova 2003gd show that dust formation in supernova ejecta can be efficient and that massive-star supernovae could have been major dust producers throughout the history of the universe.
The second data release of the INT Photometric Hα Survey of the Northern Galactic Plane (IPHAS DR2)
The INT/WFC Photometric Hα Survey of the Northern Galactic Plane (IPHAS) is a 1800 deg2 imaging survey covering Galactic latitudes |b| < 5° and longitudes l = 30°–215° in the r, i, and Hα filters
Mass-loss on the red giant branch: the value and metallicity dependence of Reimers’ η in globular clusters
The impact of metallicity on the mass-loss rate from red giant branch (RGB) stars is studied through its effect on the parameters of horizontal branch (HB) stars. The scaling factors from Reimers
Low-mass supernovae in the early Galactic halo: source of the double r/s-process enriched halo stars?
Several stars at the low-metallicity extreme of the Galactic halo ([Fe/H]= -2.5) show strong enhancements of both s-process and r-process elements. The presence of s-process elements in main-sequence
The global gas and dust budget of the Large Magellanic Cloud: AGB stars and supernovae, and the impact on the ISM evolution
We report on an analysis of the gas and dust budget in the the interstellar medium (ISM) of the Large Magellanic Cloud (LMC). Recent observations from the Spitzer Space Telescope enable us to study
Vvv dr1: the first data release of the milky way bulge and southern plane from the near-infrared eso public survey vista variables in the via lactea
Context. The ESO public survey VISTA variables in the V�a L�ctea (VVV) started in 2010. VVV targets 562 sq. deg in the Galactic bulge and an adjacent plane region and is expected to run for about
The VST Photometric Hα Survey of the Southern Galactic Plane and Bulge (VPHAS
The VST Photometric HSurvey of the Southern Galactic Plane and Bulge (VPHAS+) is surveying the southern Milky Way in u,g,r,i and Hat �1 arcsec angular resolution. Its footprint spans the Galactic