A multi-instrument and multi-wavelength high angular resolution study of MWC614: quantum heated particles inside the disk cavity
American Astronomical Society / IOP Publishing
© 2018. The American Astronomical Society. All rights reserved.
High angular resolution observations of young stellar objects are required to study the inner astronomical units of protoplanetary disks in which the majority of planets form. As they evolve, gaps open up in the inner disk regions and the disks are fully dispersed within ~10 Myrs. MWC 614 is a pre-transitional object with a ~10au radius gap. We present a set of high angular resolution observations of this object including SPHERE/ZIMPOL polarimetric and coronagraphic images in the visible, KECK/NIRC2 near-infrared aperture masking observations and VLTI (AMBER, MIDI, and PIONIER) and CHARA (CLASSIC and CLIMB) long-baseline interferometry at infrared wavelengths. We find that all the observations are compatible with an inclined disk (i ~55deg at a position angle of ~20-30deg). The mid-infrared dataset confirms the disk inner rim to be at 12.3+/-0.4 au from the central star. We determined an upper mass limit of 0.34 Msun for a companion inside the cavity. Within the cavity, the near-infrared emission, usually associated with the dust sublimation region, is unusually extended (~10 au, 30 times larger than the theoretical sublimation radius) and indicates a high dust temperature (T~1800 K). As a possible result of companion-induced dust segregation, quantum heated dust grains could explain the extended near-infrared emission with this high temperature. Our observations confirm the peculiar state of this object where the inner disk has already been accreted onto the star exposing small particles inside the cavity to direct stellar radiation.
he authors acknowledge support from a Marie Sklodowska-Curie CIG grant (Grant No. 618910), Philip Leverhulme Prize (PLP-2013-110), STFC Rutherford Fellowship (ST/J004030/1), and ERC Starting Grant (Grant Agreement No. 639889). A.A. and J.D.M. acknowledge support from NSF AAG 1311698. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of MaunaKea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. This work was supported by a NASA Keck PI Data Award, administered by the NASA Exoplanet Science Institute (PID 69/2013B_N104N2). Data presented herein were obtained at the W. M. Keck Observatory from telescope time allocated to NASA through the agency's scientific partnership with the California Institute of Technology and the University of California. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. This work is based in part upon observations obtained with the Georgia State University (GSU) Center for High Angular Resolution Astronomy Array at Mount Wilson Observatory. The CHARA Array is supported by the NSF under Grant No. AST-1211929. Institutional support has been provided from the GSU College of Arts and Sciences and the GSU Office of the Vice President for Research and Economic Development. This research has made use of the SIMBAD database and the VizieR catalog access tool, operated at CDS, Strasbourg, France.
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record
Vol. 855 (1), article 44