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Title: Protoplanetary Disk Polarization at Multiple Wavelengths: Are Dust Populations Diverse?
Abstract

Millimeter and submillimeter observations of continuum linear dust polarization provide insight into dust grain growth in protoplanetary disks, which are the progenitors of planetary systems. We present the results of the first survey of dust polarization in protoplanetary disks at 870μm and 3 mm. We find that protoplanetary disks in the same molecular cloud at similar evolutionary stages can exhibit different correlations between observing wavelength and polarization morphology and fraction. We explore possible origins for these differences in polarization, including differences in dust populations and protostar properties. For RY Tau and MWC 480, which are consistent with scattering at both wavelengths, we present models of the scattering polarization from several dust grain size distributions. These models aim to reproduce two features of the observational results for these disks: (1) both disks have an observable degree of polarization at both wavelengths; and (2) the polarization fraction is higher at 3 mm than at 870μm in the centers of the disks. For both disks, these features can be reproduced by a power-law distribution of spherical dust grains with a maximum radius of 200μm and high optical depth. In MWC 480, we can also reproduce features (1) and (2) with a model containing large grains (amax= 490μm) near the disk midplane and small grains (amax= 140μm) above and below the midplane.

 
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Award ID(s):
1910364 2307844 1910106
PAR ID:
10507644
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
967
Issue:
1
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 40
Size(s):
Article No. 40
Sponsoring Org:
National Science Foundation
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