Using the multi-object adaptive optics demonstrator RAVEN to observe metal-poor stars in and towards the Galactic Centre

• Type: Article in International Scientific Journal
• Date: 2017

Authors

Lamb, M (Author) Other; Venn, K (Author) Other; Andersen, D (Author) Other; Oya, S (Author) Other; Shetrone, M (Author) Other; Fattahi, A (Author) Other; Howes, L (Author) Other; Asplund, M (Author) Other; Lardière, O (Author) Other; Akiyama, M (Author) Other; Ono, Y (Author) Other; Terada, H (Author) Other; Hayano, Y (Author) Other; Suzuki, G (Author) Other; Blain, C (Author) Other; Jackson, K (Author) Other; Correia, C (Author) Other; Youakim, K (Author) Other; Bradley, C (Author) Other

Journal

Title: Monthly Notices of the Royal Astronomical Society

Vol. 465

Pages: 3536-3557

ISSN: 0035-8711

Publisher: Oxford University Press

Indexing

ISI Web of Knowledge - 17 Citations

Scopus - 18 Citations

Other information

Authenticus ID: P-014-ZCD

DOI: 10.1093/mnras/stw2865

Abstract (EN): 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 [¿/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 1¿, although one of these two stars has [Fe/H] = -2.01 ± 0.09, which is on the low end for this cluster. The [¿/Fe] and [Ni/Fe] values differ by 2¿, 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 multiobject 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.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 22