Cooper, HDB, Lumsden, SL, Oudmaijer, RD, Hoare, MG, Clarke, AJ, Urquhart, JS, Mottram, JC, Moore, TJT and Davies, B (2013) The RMS survey: near-IR spectroscopy of massive young stellar objects. Monthly Notices of the Royal Astronomical Society, 430 (2). pp. 1125-1157. ISSN 0035-8711

Preview

Text The RMS survey near-IR spectroscopy of massive young stellar objects.pdf - Published Version Download (1MB) | Preview

Abstract

Near-infrared H- and K-band spectra are presented for 247 objects, selected from the Red MSX Source (RMS) survey as potential young stellar objects (YSOs). 195 (∼80 per cent) of the targets are YSOs, of which 131 are massive YSOs (L BOL > 5×10 3 L ⊙ , M > 8 M ⊙ ). This is the largest spectroscopic study of massive YSOs to date, providing a valuable resource for the study of massive star formation. In this paper, we present our exploratory analysis of the data. The YSOs observed have a wide range of embeddedness (2.7 < A V < 114), demonstrating that this study covers minimally obscured objects right through to very red, dusty sources. Almost all YSOs show some evidence for emission lines, though there is a wide variety of observed properties. The most commonly detected lines are Brγ, H 2 , fluorescent Fe ii, CO bandhead, [Fe ii] and He i 2-1 1 S- 1 P, in order of frequency of occurrence. In total, ∼40 per cent of the YSOs display either fluorescent Fe ii 1.6878 μm or CO bandhead emission (or both), indicative of a circumstellar disc; however, no correlation of the strength of these lines with bolometric luminosity was found. We also find that ∼60 per cent of the sources exhibit [Fe ii] or H 2 emission, indicating the presence of an outflow. Three quarters of all sources have Brγ in emission. A good correlation with bolometric luminosity was observed for both the Brγ and H 2 emission line strengths, covering 1 < L BOL < 3.5 × 10 5 L ⊙ . This suggests that the emission mechanism for these lines is the same for low-, intermediate- and high-mass YSOs, i.e. high-mass YSOs appear to resemble scaled-up versions of low-mass YSOs. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Item Type:	Article
Additional Information:	This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2012 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
Uncontrolled Keywords:	0201 Astronomical And Space Sciences
Subjects:	Q Science > QB Astronomy Q Science > QC Physics
Divisions:	Astrophysics Research Institute
Publisher:	Oxford University Press
Related URLs:	Author
Date Deposited:	08 Mar 2018 11:42
Last Modified:	04 Sep 2021 10:41
DOI or ID number:	10.1093/mnras/sts681
URI:	https://researchonline.ljmu.ac.uk/id/eprint/8228

View Item