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Transitional disks are circumstellar disks with inner holes that in some cases are produced by planets and/or substellar companions in these systems. For this reason, these disks are extremely important for the study of planetary system formation. The Herschel Space Observatory provides an unique opportunity for studying the outer regions of protoplanetary disks. In this work we update previous knowledge on the transitional disks in the Chamaeleon I and II regions with data from the Herschel Gould Belt Survey. We propose a new method for transitional disk classification based on the WISE 12 micron-PACS 70 micron color, together with inspection of the Herschel images. We applied this method to the population of Class II sources in the Chamaeleon region and studied the spectral energy distributions of the transitional disks in the sample. We also built the median spectral energy distribution of Class II objects in these regions for comparison with transitional disks. The proposed method allows a clear separation of the known transitional disks from the Class II sources. We find 6 transitional disks, all previously known, and identify 5 objects previously thought to be transitional as possibly non-transitional. We find higher fluxes at the PACS wavelengths in the sample of transitional disks than those of Class II objects. We show the Herschel 70 micron band to be an efficient tool for transitional disk identification. The sensitivity and spatial resolution of Herschel reveals a significant contamination level among the previously identified transitional disk candidates for the two regions, which calls for a revision of previous samples of transitional disks in other regions. The systematic excess found at the PACS bands could be a result of the mechanism that produces the transitional phase, or an indication of different evolutionary paths for transitional disks and Class II sources.
Transitional disks are protoplanetary disks with opacity gaps/cavities in their dust distribution, a feature that may be linked to planet formation. We perform Bayesian modeling of the three transitional disks SZ Cha, CS Cha and T25 including photome
Context. Observations of nearby star-forming regions with the Herschel Space Observatory complement our view of the protoplanetary disks in Ophiuchus with information about the outer disks. Aims. The main goal of this project is to provide new far-in
Transitional disks around young stars are promising candidates to look for recently formed, embedded planets. Planet-disk interaction models predict that planets clear a gap in the gas while trapping dust at larger radii. Other physical mechanisms co
New data from the Herschel Space Observatory are broadening our understanding of the physics and evolution of the outer regions of protoplanetary disks in star forming regions. In particular they prove to be useful to identify transitional disk candi
Transitional disks with large dust cavities are important laboratories to study planet formation and disk evolution. Cold gas may still be present inside these cavities, but the quantification of this gas is challenging. The gas content is important