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Title: NIR spectroscopy of the HAeBe star HD 100546. III. Further evidence of an orbiting companion?

Abstract

We report high-resolution NIR spectroscopy of CO and OH emission from the Herbig Be star HD 100546. We discuss how our results bear striking resemblance to several theoretically predicted signposts of giant planet formation. The properties of the CO and OH emission lines are consistent with our earlier interpretation that these diagnostics provide indirect evidence for a companion that orbits the star close to the disk wall (at ∼13 AU). The asymmetry of the OH spectral line profiles and their lack of time variability are consistent with emission from gas in an eccentric orbit at the disk wall that is approximately stationary in the inertial frame. The time variable spectroastrometric properties of the CO v = 1-0 emission line point to an orbiting source of CO emission with an emitting area similar to that expected for a circumplanetary disk (∼0.1 AU{sup 2}) assuming the CO emission is optically thick. We also consider a counterhypothesis to this interpretation, namely that the variable CO emission arises from a bright spot on the disk wall. We conclude with a brief suggestion of further work that can distinguish between these scenarios.

Authors:
 [1];  [2];  [3]; ;  [4]
  1. Department of Physics and Astronomy, 118 Kinard Laboratory, Clemson University, Clemson, SC 29634 (United States)
  2. Naval Research Laboratory, Code 7211, Washington, DC 20375 (United States)
  3. National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States)
  4. ETH Zurich, Institute for Astronomy, Wolfgang-Pauli-Strasse 27, 8093 Zurich (Switzerland)
Publication Date:
OSTI Identifier:
22365275
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 791; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; APPROXIMATIONS; ASYMMETRY; CARBON MONOXIDE; EMISSION; NEAR INFRARED RADIATION; ORBITS; PLANETS; PROTOPLANETS; RESOLUTION; STARS

Citation Formats

Brittain, Sean D., Carr, John S., Najita, Joan R., Quanz, Sascha P., and Meyer, Michael R., E-mail: sbritt@clemson.edu. NIR spectroscopy of the HAeBe star HD 100546. III. Further evidence of an orbiting companion?. United States: N. p., 2014. Web. doi:10.1088/0004-637X/791/2/136.
Brittain, Sean D., Carr, John S., Najita, Joan R., Quanz, Sascha P., & Meyer, Michael R., E-mail: sbritt@clemson.edu. NIR spectroscopy of the HAeBe star HD 100546. III. Further evidence of an orbiting companion?. United States. doi:10.1088/0004-637X/791/2/136.
Brittain, Sean D., Carr, John S., Najita, Joan R., Quanz, Sascha P., and Meyer, Michael R., E-mail: sbritt@clemson.edu. Wed . "NIR spectroscopy of the HAeBe star HD 100546. III. Further evidence of an orbiting companion?". United States. doi:10.1088/0004-637X/791/2/136.
@article{osti_22365275,
title = {NIR spectroscopy of the HAeBe star HD 100546. III. Further evidence of an orbiting companion?},
author = {Brittain, Sean D. and Carr, John S. and Najita, Joan R. and Quanz, Sascha P. and Meyer, Michael R., E-mail: sbritt@clemson.edu},
abstractNote = {We report high-resolution NIR spectroscopy of CO and OH emission from the Herbig Be star HD 100546. We discuss how our results bear striking resemblance to several theoretically predicted signposts of giant planet formation. The properties of the CO and OH emission lines are consistent with our earlier interpretation that these diagnostics provide indirect evidence for a companion that orbits the star close to the disk wall (at ∼13 AU). The asymmetry of the OH spectral line profiles and their lack of time variability are consistent with emission from gas in an eccentric orbit at the disk wall that is approximately stationary in the inertial frame. The time variable spectroastrometric properties of the CO v = 1-0 emission line point to an orbiting source of CO emission with an emitting area similar to that expected for a circumplanetary disk (∼0.1 AU{sup 2}) assuming the CO emission is optically thick. We also consider a counterhypothesis to this interpretation, namely that the variable CO emission arises from a bright spot on the disk wall. We conclude with a brief suggestion of further work that can distinguish between these scenarios.},
doi = {10.1088/0004-637X/791/2/136},
journal = {Astrophysical Journal},
number = 2,
volume = 791,
place = {United States},
year = {Wed Aug 20 00:00:00 EDT 2014},
month = {Wed Aug 20 00:00:00 EDT 2014}
}
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