Low Metallicity Indicates That the Hypervelocity Star HE 0437-5439 was Ejected from the Large Magellanic Cloud
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منابع مشابه
Low Metallicity Indicates that the Hypervelocity Star HE 0437–5439 was Ejected from the LMC
We measure the metallicity of the unusual hypervelocity star HE 0437–5439 from high resolution spectroscopy to be half-solar. We determine a spectral type of B2 IV-III for the star and derive an effective temperature Teff = 21,500 ± 1,000 K and a surface gravity log(g) = 3.7 ± 0.2 (cgs). We also present BV time series photometry and find the star to be non-variable at the 0.02 mag level. We ref...
متن کاملA hypervelocity star from the Large Magellanic Cloud
We study the acceleration of the star HE 0437–5439 to hypervelocity and discuss its possible origin in the Large Magellanic Cloud (LMC). The star has a radial velocity of 723 km s and is located at a distance of 61 kpc from the Sun. With a mass of about 8M⊙, the travel time from the Galactic centre is of about 100Myr, much longer than its main sequence lifetime. Given the relatively small dista...
متن کاملHe 0437−5439 – an Unbound Hyper-velocity Main-sequence B-type Star *
We report the discovery of a 16 th magnitude star, HE 0437−5439, with a heliocentric radial velocity of +723 ± 3 km s −1. A quantitative spectral analysis of high-resolution optical spectra obtained with the VLT and the UVES – 2 – spectrograph shows that HE 0437−5439 is a main sequence B-type star with T eff =20 350 K, log(g) = 3.77, solar within a factor of a few helium abundance and metal con...
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We have estimated a metallicity map of the Large Magellanic Cloud (LMC) using the Magellanic Cloud Photometric Survey (MCPS) and Optical Gravitational Lensing Experiment (OGLE III) photometric data. This is a first of its kind map of metallicity up to a radius of 4◦–5◦, derived using photometric data and calibrated using spectroscopic data of Red Giant Branch (RGB) stars. We identify the RGB in...
متن کاملThe Star Formation History of the Large Magellanic Cloud
We present the first-ever global, spatially-resolved reconstruction of the star formation history (SFH) of the Large Magellanic Cloud (LMC), based on the application of our StarFISH analysis software to the multiband photometry of twenty million of its stars from the Magellanic Clouds Photometric Survey. The general outlines of our results are consistent with previously published results: follo...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2008
ISSN: 0004-637X,1538-4357
DOI: 10.1086/533531