The GRAVITY young stellar object survey: II. First spatially resolved observations of the CO bandhead emission in a high-mass YSO
Artikel i vetenskaplig tidskrift, 2020
Context. The inner regions of the discs of high-mass young stellar objects (HMYSOs) are still poorly known due to the small angular scales and the high visual extinction involved. Aims. We deploy near-infrared spectro-interferometry to probe the inner gaseous disc in HMYSOs and investigate the origin and physical characteristics of the CO bandhead emission (2.3-2.4 m). Methods. We present the first GRAVITY/VLTI observations at high spectral (R = 4000) and spatial (mas) resolution of the CO overtone transitions in NGC2024 IRS 2. Results. The continuum emission is resolved in all baselines and is slightly asymmetric, displaying small closure phases (8). Our best ellipsoid model provides a disc inclination of 34 1, a disc major axis position angle (PA) of 166 1, and a disc diameter of 3:99 0:09 mas (or 1.69 0.04 au, at a distance of 423 pc). The small closure phase signals in the continuum are modelled with a skewed rim, originating from a pure inclination effect. For the first time, our observations spatially and spectrally resolve the first four CO bandheads. Changes in visibility, as well as differential and closure phases across the bandheads are detected. Both the size and geometry of the CO-emitting region are determined by fitting a bidimensional Gaussian to the continuum-compensated CO bandhead visibilities. The CO-emitting region has a diameter of 2.740:08 0:07 mas (1.16 0.03 au), and is located in the inner gaseous disc, well within the dusty rim, with inclination and PA matching the dusty disc geometry, which indicates that both dusty and gaseous discs are coplanar. Physical and dynamical gas conditions are inferred by modelling the CO spectrum. Finally, we derive a direct measurement of the stellar mass of M 14:7 M by combining our interferometric and spectral modelling results.
Techniques: spectroscopic
Methods: observational
Infrared: stars
Techniques: interferometric
Stars: massive
Stars: formation
Författare
A. Caratti o. Garatti
Dublin Institute for Advanced Studies
Max-Planck-Gesellschaft
University College Dublin
Rubén Fedriani
Dublin Institute for Advanced Studies
University College Dublin
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
R. Garcia-Lopez
Max-Planck-Gesellschaft
Dublin Institute for Advanced Studies
University College Dublin
M. Koutoulaki
Dublin Institute for Advanced Studies
University College Dublin
European Southern Observatory (ESO)
K. Perraut
Université Grenoble Alpes
H. Linz
Max-Planck-Gesellschaft
W. Brandner
Max-Planck-Gesellschaft
P. J. V. Garcia
Universidade do Porto
Instituto Superior Tecnico
European Southern Observatory Santiago
L. Klarmann
Max-Planck-Gesellschaft
T. Henning
Max-Planck-Gesellschaft
L. Labadie
Universität zu Köln
J. Sanchez-Bermudez
Max-Planck-Gesellschaft
Universidad Nacional Autónoma de México
B. Lazareff
Université Grenoble Alpes
E. F. van Dishoeck
Universiteit Leiden
Max-Planck-Gesellschaft
P. Caselli
Max-Planck-Gesellschaft
P. T. De Zeeuw
Max-Planck-Gesellschaft
Universiteit Leiden
A. Bik
Stockholms universitet
M. Benisty
European Southern Observatory Santiago
Université Grenoble Alpes
C. Dougados
Université Grenoble Alpes
Tom Ray
Dublin Institute for Advanced Studies
A. Amorim
Instituto Superior Tecnico
J. P. Berger
Université Grenoble Alpes
Y. Clénet
Observatoire de Paris
V. Coudé Du Foresto
Observatoire de Paris
G. Duvert
Université Grenoble Alpes
A. Eckart
Universität zu Köln
F. Eisenhauer
Max-Planck-Gesellschaft
F. Gao
Max-Planck-Gesellschaft
E. Gendron
Observatoire de Paris
R. Genzel
University of California
Max-Planck-Gesellschaft
S. Gillessen
Max-Planck-Gesellschaft
P. Gordo
Instituto Superior Tecnico
L. Jocou
Université Grenoble Alpes
M. Horrobin
Universität zu Köln
P. Kervella
Observatoire de Paris
S. Lacour
Observatoire de Paris
J. B. Le Bouquin
Université Grenoble Alpes
P. Léna
Observatoire de Paris
R. Grellmann
Universität zu Köln
T. Ott
Max-Planck-Gesellschaft
T. Paumard
Observatoire de Paris
G. Perrin
Observatoire de Paris
G. Rousset
Observatoire de Paris
S. Scheithauer
Max-Planck-Gesellschaft
J. Shangguan
Max-Planck-Gesellschaft
J. Stadler
Max-Planck-Gesellschaft
O. Straub
Max-Planck-Gesellschaft
C. Straubmeier
Universität zu Köln
E. Sturm
Max-Planck-Gesellschaft
W. F. Thi
Max-Planck-Gesellschaft
F. H. Vincent
Observatoire de Paris
F. Widmann
Max-Planck-Gesellschaft
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 635 L12Ämneskategorier
Meteorologi och atmosfärforskning
Astronomi, astrofysik och kosmologi
Atom- och molekylfysik och optik
DOI
10.1051/0004-6361/202037583