Using the multi-object adaptive optics demonstrator RAVEN to observe metal-poor stars in and towards the Galactic Centre
Creators
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1.
University of Victoria
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2.
Herzberg Institute of Astrophysics
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3.
University of Hawaii at Hilo
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4.
The University of Texas at Austin
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5.
Australian National University
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6.
Lund University
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7.
Tohoku University
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8.
California Institute of Technology
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9.
Aix-Marseille University
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10.
Leibniz Institute for Astrophysics Potsdam
Abstract
The chemical abundances for five metal-poor stars in and towards the Galactic bulge have been determined from the H-band infrared spectroscopy taken with the RAVEN multi-object adaptive optics science demonstrator and the Infrared Camera and Spectrograph at the Subaru 8.2-m telescope. Three of these stars are in the Galactic bulge and have metallicities between −2.1 < [Fe/H] < −1.5, and high [α/Fe] ∼ +0.3, typical of Galactic disc and bulge stars in this metallicity range; [Al/Fe] and [N/Fe] are also high, whereas [C/Fe] < +0.3. An examination of their orbits suggests that two of these stars may be confined to the Galactic bulge and one is a halo trespasser, though proper motion values used to calculate orbits are quite uncertain. An additional two stars in the globular cluster M22 show [Fe/H] values consistent to within 1σ, although one of these two stars has [Fe/H] = −2.01 ± 0.09, which is on the low end for this cluster. The [α/Fe] and [Ni/Fe] values differ by 2σ, with the most metal-poor star showing significantly higher values for these elements. M22 is known to show element abundance variations, consistent with a multipopulation scenario though our results cannot discriminate this clearly given our abundance uncertainties. This is the first science demonstration of multi-object adaptive optics with high-resolution infrared spectroscopy, and we also discuss the feasibility of this technique for use in the upcoming era of 30-m class telescope facilities.
Additional Information
© 2016 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. Received: 20 September 2016. Revision Received: 02 November 2016. Accepted: 03 November 2016. Published: 05 November 2016. This paper is based (in part) on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. We are sincerely grateful to the RAVEN team, and the support of the Subaru staff during our engineering runs. MPL and KAV also acknowledge funding from an NSERC Discovery Grant to help fund this research.Attached Files
Published - stw2865.pdf
Submitted - 1611.02712.pdf
Files
1611.02712.pdf
Additional details
Identifiers
- Eprint ID
- 76628
- Resolver ID
- CaltechAUTHORS:20170418-083220534
Related works
- Describes
- https://arxiv.org/abs/1611.02712 (URL)
Funding
- Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant
Dates
- Created
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2017-04-18Created from EPrint's datestamp field
- Updated
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2021-11-15Created from EPrint's last_modified field