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arXiv · 0803.3606

Gas and dust in the inner disk of the Herbig Ae star MWC 758

A. Isella·E. Tatulli·A. Natta·L. Testi
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Abstract

In this Letter we investigate the origin of the near-infrared emission of the Herbig Ae star MWC 758 on sub-astronomical unit (AU) scales using spectrally dispersed low resolution (R=35) AMBER/VLTI interferometric observations both in the H ($1.7 \mu$m) and K ($2.2 \mu$m) bands. We find that the K band visibilities and closure phases are consistent with the presence of a dusty disk inner rim located at the dust evaporation distance (0.4 AU) while the bulk of the H band emission arises within 0.1 AU from the central star. Comparing the observational results with theoretical model predictions, we suggest that the H band emission is dominated by an hot gaseous accretion disk.

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A. Isella, E. Tatulli, A. Natta, L. Testi. 2008-03-25. Gas and dust in the inner disk of the Herbig Ae star MWC 758. https://doi.org/10.1051/0004-6361:200809641

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