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Post Info TOPIC: QSO J0035-0918
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Wreckage is from 'pristine star'

UK and US scientists have found the remnants of a star that exploded more than 13 billion years ago.
It would most probably have been one of the very first stars to shine in the Universe, they say.
All that is left of this pioneer is the gas cloud it threw out into space when it blew itself apart.
It was identified when its contents were illuminated by the brilliant light coming from the surroundings of a distant black hole.
The cloud's atoms occur in abundances that are quite unlike that found in the nearby cosmos today and are more what one would expect from stars that were originally made only of hydrogen and helium.
The research required the observations of two of the world's most powerful telescopes - the Keck facility in Hawaii and the Very Large Telescope in Chile.
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Title: A Carbon-enhanced Metal-poor Damped Lyman alpha System: Probing Gas from Population III Nucleosynthesis?
Authors: Ryan Cooke (Institute of Astronomy, University of Cambridge), Max Pettini (Institute of Astronomy, University of Cambridge), Charles C. Steidel (California Institute of Technology), Gwen C. Rudie (California Institute of Technology), Regina A. Jorgenson (Institute of Astronomy, University of Cambridge)
(Version v2)

We present high resolution observations of an extremely metal-poor damped Lyman-alpha system, at z_abs = 2.3400972 in the spectrum of the QSO J0035-0918, exhibiting an abundance pattern consistent with model predictions for the supernova yields of Population III stars. Specifically, this DLA has [Fe/H] = -3.04, shows a clear 'odd-even' effect, and is C-rich with [C/Fe] = +1.53, a factor of about 20 greater than reported in any other damped Lyman-alpha system. In analogy to the carbon-enhanced metal-poor stars in the Galactic halo (with [C/Fe] > +1.0), this is the first reported case of a carbon-enhanced damped Lyman-alpha system. We determine an upper limit to the mass of 12C, M(12C) < 200 solar masses, which depends on the unknown gas density n(H); if n(H) > 1 atom per cubic cm (which is quite likely for this DLA given its low velocity dispersion), then M(12C) < 2 solar masses, consistent with pollution by only a few prior supernovae. We speculate that DLAs such as the one reported here may represent the 'missing link' between the yields of Pop III stars and their later incorporation in the class of carbon-enhanced metal-poor stars which show no enhancement of neutron-capture elements (CEMP-no stars).

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