ALMA REVEALS THE ANATOMY OF THE mm-SIZED DUST AND MOLECULAR GAS IN THE HD 97048 DISK

作者:Walsh Catherine; Juhasz Attila; Meeus Gwendolyn; Dent William R F; Maud Luke T; Aikawa Yuri; Millar Tom J; Nomura Hideko
来源:Astrophysical Journal, 2016, 831(2): 200.
DOI:10.3847/0004-637X/831/2/200

摘要

Transitional disks show a lack of excess emission at infrared wavelengths due to a large dust cavity, that is often corroborated by spatially resolved observations at similar to mm wavelengths. We present the first spatially resolved similar to mm-wavelength images of the disk around the Herbig Ae/Be star, HD 97048. Scattered light images show that the disk extends to approximate to 640 au. ALMA data reveal a circular-symmetric dusty disk extending to approximate to 350 au, and a molecular disk traced in CO J - 3-2 emission, extending to approximate to 750 au. The CO emission arises from a flared layer with an opening angle approximate to 30 degrees-40 degrees. HD. 97048 is another source for which the large (similar to mm-sized) dust grains are more centrally concentrated than the small (similar to mu m-sized) grains and molecular gas, likely due to radial drift. The images and visibility data modeling suggest a decrement in continuum emission within approximate to 50 au, consistent with the cavity size determined from mid-infrared imaging ( 34 +/- 4 au). The extracted continuum intensity profiles show ring-like structures with peaks at approximate to 50, 150, and 300 au, with associated gaps at approximate to 100 and 250 au. This structure should be confirmed in higher-resolution images (FWHM approximate to 10-20 au). These data confirm the classification of HD. 97048 as a transitional disk that also possesses multiple ring-like structures in the dust continuum emission. Additional data are required at multiple and well-separated frequencies to fully characterize the disk structure, and thereby constrain the mechanism(s) responsible for sculpting the HD. 97048 disk.

  • 出版日期2016-11-10