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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 ~ mm wavelengths. We present the first spatially resolved ~ mm-wavelength images of the disk around the Herbig Ae/Be star, HD 97048. Scattered light images show that the disk extends to ~640 au. The ALMA data reveal a circular-symmetric dusty disk extending to ~350 au, and a molecular disk traced in CO J=3-2 emission, extending to ~750 au. The CO emission arises from a flared layer with an opening angle ~ 30 deg - 40 deg. HD 97048 is another source for which the large (~ mm-sized) dust grains are more centrally concentrated than the small (~ {mu}m-sized) grains and molecular gas, likely due to radial drift. The images and visibility data modelling suggests a decrement in continuum emission within ~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 ~50, 150, and 300 au, with associated gaps at ~100 and 250 au. This structure should be confirmed in higher-resolution images (FWHM ~ 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 characterise the disk structure, and thereby constrain the mechanism(s) responsible for sculpting the HD 97048 disk.
The combination of high resolution and sensitivity offered by ALMA is revolutionizing our understanding of protoplanetary discs, as their bulk gas and dust distributions can be studied independently. In this paper we present resolved ALMA observation
We present new Atacama Large Millimeter/sub-millimeter Array (ALMA) 1.3 mm continuum observations of the SR 24S transition disk with an angular resolution $lesssim0.18$ (12 au radius). We perform a multi-wavelength investigation by combining new data
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