Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
VLTI/AMBER spectro-interferometry of the Herbig Be star MWC 297 with spectral resolution 12000. / Weigelt, G.; Grinin, V. P.; Groh, J. H.; Hofmann, K. H.; Kraus, S.; Miroshnichenko, A. S.; Schertl, D.; Tambovtseva, L. V.; Benisty, M.; Driebe, T.; Lagarde, S.; Malbet, F.; Meilland, A.; Petrov, R.; Tatulli, E.
в: Astronomy and Astrophysics, Том 527, № 13, A103, 03.2011.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - VLTI/AMBER spectro-interferometry of the Herbig Be star MWC 297 with spectral resolution 12000
AU - Weigelt, G.
AU - Grinin, V. P.
AU - Groh, J. H.
AU - Hofmann, K. H.
AU - Kraus, S.
AU - Miroshnichenko, A. S.
AU - Schertl, D.
AU - Tambovtseva, L. V.
AU - Benisty, M.
AU - Driebe, T.
AU - Lagarde, S.
AU - Malbet, F.
AU - Meilland, A.
AU - Petrov, R.
AU - Tatulli, E.
PY - 2011/3
Y1 - 2011/3
N2 - Context. Circumstellar disks and outflows play a fundamental role in star formation. Infrared spectro-interferometry allows the inner accretion-ejection region to be resolved. Aims. We study the disk and Brγ-emitting region of MWC 297 with high spatial and spectral resolution and compare our observations with disk-wind models. Methods. We measured interferometric visibilities, wavelength-differential phases, and closure phases of MWC 297 with a spectral resolution of 12 000. To interpret our MWC 297 observations, we employed disk-wind models. Results. The measured continuum visibilities confirm previous results that the continuum-emitting region of MWC 297 is remarkably compact. We derive a continuum ring-fit radius of ∼2.2 mas (∼0.56 AU at a distance of 250 pc), which is ~5.4 times smaller than the 3 AU dust sublimation radius expected for silicate grains (in the absence of radiation-shielding material). The strongly wavelength-dependent and asymmetric Brγ-emitting region is more extended (∼2.7 times) than the continuum-emitting region. At the center of the Brγ line, we derive a Gaussian fit radius of ∼6.3 mas HWHM (∼1.6 AU). To interpret the observations, we employ a magneto-centrifugally driven disk-wind model consisting of an accretion disk, which emits the observed continuum radiation, and a disk wind, which emits the Brγ line. The calculated wavelength-dependent model intensity distributions and Brγ line profiles are compared with the observations (i.e., K-band spectrum, visibilities, differential phases, and closure phases). The closest fitting model predicts a continuum-emitting disk with an inner radius of ∼0.3 AU and a disk wind ejection region with an inner radius of ∼0.5 AU (∼17.5 stellar radii). We obtain a disk-wind half-opening angle (the angle between the rotation axis and the innermost streamline of the disk wind) of ∼80°, which is larger than in T Tau models, and a disk inclination angle of ∼20° (i.e., almost pole-on). Conclusions. Our observations with a spectral resolution of 12 000 allow us to study the AU-scale environment of MWC 297 in ∼10 different spectral channels across the Brγ emission line. We show that the K-band flux, visibilities, and remarkably strong phases can be explained by the employed magneto-centrifugally driven disk wind model.
AB - Context. Circumstellar disks and outflows play a fundamental role in star formation. Infrared spectro-interferometry allows the inner accretion-ejection region to be resolved. Aims. We study the disk and Brγ-emitting region of MWC 297 with high spatial and spectral resolution and compare our observations with disk-wind models. Methods. We measured interferometric visibilities, wavelength-differential phases, and closure phases of MWC 297 with a spectral resolution of 12 000. To interpret our MWC 297 observations, we employed disk-wind models. Results. The measured continuum visibilities confirm previous results that the continuum-emitting region of MWC 297 is remarkably compact. We derive a continuum ring-fit radius of ∼2.2 mas (∼0.56 AU at a distance of 250 pc), which is ~5.4 times smaller than the 3 AU dust sublimation radius expected for silicate grains (in the absence of radiation-shielding material). The strongly wavelength-dependent and asymmetric Brγ-emitting region is more extended (∼2.7 times) than the continuum-emitting region. At the center of the Brγ line, we derive a Gaussian fit radius of ∼6.3 mas HWHM (∼1.6 AU). To interpret the observations, we employ a magneto-centrifugally driven disk-wind model consisting of an accretion disk, which emits the observed continuum radiation, and a disk wind, which emits the Brγ line. The calculated wavelength-dependent model intensity distributions and Brγ line profiles are compared with the observations (i.e., K-band spectrum, visibilities, differential phases, and closure phases). The closest fitting model predicts a continuum-emitting disk with an inner radius of ∼0.3 AU and a disk wind ejection region with an inner radius of ∼0.5 AU (∼17.5 stellar radii). We obtain a disk-wind half-opening angle (the angle between the rotation axis and the innermost streamline of the disk wind) of ∼80°, which is larger than in T Tau models, and a disk inclination angle of ∼20° (i.e., almost pole-on). Conclusions. Our observations with a spectral resolution of 12 000 allow us to study the AU-scale environment of MWC 297 in ∼10 different spectral channels across the Brγ emission line. We show that the K-band flux, visibilities, and remarkably strong phases can be explained by the employed magneto-centrifugally driven disk wind model.
KW - circumstellar matter
KW - stars: individual: MWC 297
KW - stars: pre-main sequence
KW - stars: winds, outflows
KW - techniques: interferometric
KW - techniques: spectroscopic
UR - http://www.scopus.com/inward/record.url?scp=79551655304&partnerID=8YFLogxK
U2 - 10.1051/0004-6361/201015676
DO - 10.1051/0004-6361/201015676
M3 - Article
AN - SCOPUS:79551655304
VL - 527
JO - ASTRONOMY & ASTROPHYSICS
JF - ASTRONOMY & ASTROPHYSICS
SN - 0004-6361
IS - 13
M1 - A103
ER -
ID: 87424727