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Title: GAPS IN PROTOPLANETARY DISKS AS SIGNATURES OF PLANETS. III. POLARIZATION

Abstract

Polarimetric observations of T Tauri and Herbig Ae/Be stars are a powerful way to image protoplanetary disks. However, interpretation of these images is difficult because the degree of polarization is highly sensitive to the angle of scattering of stellar light off the disk surface. We examine how disks with and without gaps created by planets appear in scattered polarized light as a function of inclination angle. Isophotes of inclined disks without gaps are distorted in polarized light, giving the appearance that the disks are more eccentric or more highly inclined than they truly are. Apparent gap locations are unaffected by polarization, but the gap contrast changes. In face-on disks with gaps, we find that the brightened far edge of the gap scatters less polarized light than the rest of the disk, resulting in slightly decreased contrast between the gap trough and the brightened far edge. In inclined disks, gaps can take on the appearance of being localized “holes” in brightness rather than full axisymmetric structures. Photocenter offsets along the minor axis of the disk in both total intensity and polarized intensity images can be readily explained by the finite thickness of the disk. Alone, polarized scattered light images of disksmore » do not necessarily reveal intrinsic disk structure. However, when combined with total intensity images, the orientation of the disk can be deduced and much can be learned about disk structure and dust properties.« less

Authors:
 [1]
  1. Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States)
Publication Date:
OSTI Identifier:
22664020
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 835; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AUGER ELECTRON SPECTROSCOPY; AXIAL SYMMETRY; BRIGHTNESS; DETECTION; DUSTS; INCLINATION; INTERACTIONS; PLANETS; POLARIZATION; PROTOPLANETS; SATELLITES; SCATTERING; STARS; SURFACES; THICKNESS; VISIBLE RADIATION

Citation Formats

Jang-Condell, Hannah. GAPS IN PROTOPLANETARY DISKS AS SIGNATURES OF PLANETS. III. POLARIZATION. United States: N. p., 2017. Web. doi:10.3847/1538-4357/835/1/12.
Jang-Condell, Hannah. GAPS IN PROTOPLANETARY DISKS AS SIGNATURES OF PLANETS. III. POLARIZATION. United States. doi:10.3847/1538-4357/835/1/12.
Jang-Condell, Hannah. Fri . "GAPS IN PROTOPLANETARY DISKS AS SIGNATURES OF PLANETS. III. POLARIZATION". United States. doi:10.3847/1538-4357/835/1/12.
@article{osti_22664020,
title = {GAPS IN PROTOPLANETARY DISKS AS SIGNATURES OF PLANETS. III. POLARIZATION},
author = {Jang-Condell, Hannah},
abstractNote = {Polarimetric observations of T Tauri and Herbig Ae/Be stars are a powerful way to image protoplanetary disks. However, interpretation of these images is difficult because the degree of polarization is highly sensitive to the angle of scattering of stellar light off the disk surface. We examine how disks with and without gaps created by planets appear in scattered polarized light as a function of inclination angle. Isophotes of inclined disks without gaps are distorted in polarized light, giving the appearance that the disks are more eccentric or more highly inclined than they truly are. Apparent gap locations are unaffected by polarization, but the gap contrast changes. In face-on disks with gaps, we find that the brightened far edge of the gap scatters less polarized light than the rest of the disk, resulting in slightly decreased contrast between the gap trough and the brightened far edge. In inclined disks, gaps can take on the appearance of being localized “holes” in brightness rather than full axisymmetric structures. Photocenter offsets along the minor axis of the disk in both total intensity and polarized intensity images can be readily explained by the finite thickness of the disk. Alone, polarized scattered light images of disks do not necessarily reveal intrinsic disk structure. However, when combined with total intensity images, the orientation of the disk can be deduced and much can be learned about disk structure and dust properties.},
doi = {10.3847/1538-4357/835/1/12},
journal = {Astrophysical Journal},
number = 1,
volume = 835,
place = {United States},
year = {Fri Jan 20 00:00:00 EST 2017},
month = {Fri Jan 20 00:00:00 EST 2017}
}
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