ALMA observations of the vibrationally excited rotational CO transition v = 1, J = 3 - 2 towards five AGB stars
Artikel i vetenskaplig tidskrift, 2016

We report the serendipitous detection with the Atacama Large Millimeter/submillimeter Array (ALMA) of the vibrationally excited pure-rotational CO transition v = 1, J = 3 - 2 towards five asymptotic giant branch (AGB) stars, o Cet, R Aqr, R Scl, W Aql, and ?1 Gru. The observed lines are formed in the poorly understood region located between the stellar surface and the region where the wind starts, the so-called warm molecular layer. We successfully reproduce the observed lines profiles using a simple model. We constrain the extents, densities, and kinematics of the region where the lines are produced. R Aqr and R Scl show inverse P-Cygni line profiles which indicate infall of material on to the stars. The line profiles of o Cet and R Scl show variability. The serendipitous detection towards these five sources shows that vibrationally excited rotational lines can be observed towards a large number of nearby AGB stars using ALMA. This opens a new possibility for the study of the innermost regions of AGB circumstellar envelopes. © 2016 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Circumstellar mattercover-date

Line: profiles

Stars: AGB and post-AGB

Författare

Theo Khouri

Chalmers, Rymd- och geovetenskap, Radioastronomi och astrofysik

Wouter Vlemmings

Chalmers, Rymd- och geovetenskap, Onsala rymdobservatorium

Chalmers, Rymd- och geovetenskap, Radioastronomi och astrofysik

S. Ramstedt

Uppsala universitet

Robin Lombaert

Chalmers, Rymd- och geovetenskap, Radioastronomi och astrofysik

Matthias Maercker

Chalmers, Rymd- och geovetenskap, Radioastronomi och astrofysik

Chalmers, Rymd- och geovetenskap, Onsala rymdobservatorium

Elvire De Beck

Chalmers, Rymd- och geovetenskap, Onsala rymdobservatorium

Monthly Notices of the Royal Astronomical Society: Letters

17453925 (ISSN) 17453933 (eISSN)

Vol. 463 1 L74-L78

Ämneskategorier

Astronomi, astrofysik och kosmologi

Fundament

Grundläggande vetenskaper

Infrastruktur

Onsala rymdobservatorium

DOI

10.1093/mnrasl/slw161