Cool carbon stars in the halo: new very red or distant objects

Abstract

The goal of this paper is to present and analyse a new sample of cool carbon (C)stars located in the halo. Twenty three new C stars were discovered. Spectra are typical of N-type stars with C2 and CN bands and sometimes Halpha in emission. ... Four objects are particularly red with J-K > 3, with 2 located at more than 5 kpc. from the Galactic plane. Eight additional objects with similar properties are found in the literature and our previous works. These 12 C stars could be useful to study mass loss at low metallicity. Two objects are at distances of 95 and 110 kpc. They are located in the region with galactocentric Z < -60 kpc in which the model of Law et al. predicts the Sgr stream to have a loop. (Abstact abridged)

arXiv comment16 pages, 12 figures, accepted by AA

References in corpus (16)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• The USNO-B Catalog
• A 2MASS All-Sky View of the Sagittarius Dwarf Galaxy: I. Morphology of the Sagittarius Core and Tidal Arms
• The Field of Streams: Sagittarius and its Siblings
• Northern Sky Variability Survey (NSVS): Public data release
• Great Circle tidal streams: evidence for a nearly spherical massive dark halo around the Milky Way
• Meeting the Cool New Neighbors V: A 2MASS-Selected Sample of Ultracool Dwarfs
• A 2MASS All-Sky View of the Sagittarius Dwarf Galaxy: IV. Modeling the Sagittarius Tidal Tails
• The Origin of the Bifurcation in the Sagittarius Stream
• Stellar Populations in the Large Magellanic Cloud from 2MASS
• Sagittarius Tidal Debris 90 kpc from the Galactic Center
• Reprocessing the Hipparcos data for evolved stars III Revised Hipparcos period-luminosity relationship for galactic long-period variable stars
• Carbon star populations in systems with different metallicities: statistics in Local Group galaxies
• Cool carbon stars in the halo: a new survey based on 2MASS
• Cool carbon stars in the halo II. A study of 25 new objects
• Populations of AGB stars and LPVs in the Galaxy and Local Group

Cited by in corpus (8)

• Tracing the tidal streams of the Sagittarius dSph, and halo Milky Way features, with carbon-rich long-period variables
• New observations of cool carbon stars in the halo
• The low wind expansion velocity of metal-poor carbon stars in the Halo and the Sagittarius stream
• Carbon Stars in the Satellites and Halo of M31
• Detecting Variability in Massive Astronomical Time-Series Data II: Variable Candidates in the Northern Sky Variability Survey
• Cool carbon stars in the halo and in dwarf galaxies: Halpha, colours, and variabiity
• The dust and gas content of carbon stars toward the Galactic Halo
• CGCS 6306, another X-ray-emitting asymptotic giant branch star confirmed to be a symbiotic binary