OH/IR stars and their superwinds as observed by the Herschel Space Observatory

Justtanont, K., Teyssier, D., Barlow, M. J., Matsuura, Mikako ORCID: https://orcid.org/0000-0002-5529-5593, Swinyard, B., Waters, L. B. F. M. and Yates, J. 2013. OH/IR stars and their superwinds as observed by the Herschel Space Observatory. Astronomy and Astrophysics 556 , A101. 10.1051/0004-6361/201321812

Preview

PDF - Published Version Download (812kB) | Preview

Abstract

Aims. In order to study the history of mass loss in extreme OH/IR stars, we observed a number of these objects using CO as a tracer of the density and temperature structure of their circumstellar envelopes. Methods. Combining CO observations from the Herschel Space Observatory with those from the ground, we trace mass loss rates as a function of radius in five extreme OH/IR stars. Using radiative transfer modelling, we modelled the dusty envelope as well as the CO emission. The high-rotational transitions of CO indicate that they originate in a dense superwind region close to the star while the lower transitions tend to come from a more tenuous outer wind which is a result of the mass loss since the early AGB phase. Results. The models of the circumstellar envelopes around these stars suggest that they have entered a superwind phase in the past 200–500 years. The low 18O/17O (~0.1 compared to the solar abundance ratio of ~5) and 12C/13C (3–30 cf. the solar value of 89) ratios derived from our study support the idea that these objects have undergone hot-bottom burning and hence that they are massive M ≥ 5 M⊙ AGB stars.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Physics and Astronomy
Subjects:	Q Science > QB Astronomy
Publisher:	EDP Sciences
ISSN:	0004-6361
Date of First Compliant Deposit:	13 February 2018
Date of Acceptance:	7 June 2013
Last Modified:	05 May 2023 02:05
URI:	https://orca.cardiff.ac.uk/id/eprint/109076

Citation Data

Cited 24 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item