Surface geometry of protoplanetary disks inferred from near-infrared imaging polarimetry

Journal Article · Sat Nov 01 00:00:00 EDT 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/795/1/71· OSTI ID:22370299

Takami, Michihiro; Hasegawa, Yasuhiro; Gu, Pin-Gao; Karr, Jennifer L.; Chapillon, Edwige; Tang, Ya-Wen ^[1]; Muto, Takayuki ^[2]; Dong, Ruobing ^[3]; Hashimoto, Jun ^[4]; Kusakabe, Nobuyuki; Akiyama, Eiji; Kwon, Jungmi ^[5]; Itoh, Youchi ^[6]; Carson, Joseph ^[7]; Follette, Katherine B. ^[8]; Mayama, Satoshi ^[9]; Sitko, Michael ^[10]; Janson, Markus ^[11]; Grady, Carol A. ^[12]; Kudo, Tomoyuki ^[13] ; others, and

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1. Institute of Astronomy and Astrophysics, Academia Sinica, PO Box 23-141, Taipei 10617, Taiwan, ROC (China)
2. Division of Liberal Arts, Kogakuin University, 1-24-2, Nishi-Shinjuku, Shinjuku-ku, Tokyo 163-8677 (Japan)
3. Nuclear Science Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)
4. H. L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St. Norman, OK 73019 (United States)
5. National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
6. Nishi-Harima Astronomical Observatory, Center for Astronomy, University of Hyogo, 407-2 Nishigaichi, Sayo, Sayo, Hyogo 679-5313 (Japan)
7. Department of Physics and Astronomy, College of Charleston, 58 Coming Street, Charleston, SC 29424 (United States)
8. Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)
9. The Center for the Promotion of Integrated Sciences, The Graduate University for Advanced Studies (SOKENDAI), Shonan International Village, Hayama-cho, Miura-gun, Kanagawa 240-0193 (Japan)
10. Department of Physics, University of Cincinnati, Cincinnati, OH 45221 (United States)
11. Astrophysics Research Center, Queen's University Belfast, BT7 1NN (United Kingdom)
12. Eureka Scientific, 2452 Delmer Suite 100, Oakland, CA 96402 (United States)
13. Subaru Telescope, 650 North Aohoku Place, Hilo, HI 96720 (United States)

We present a new method of analysis for determining the surface geometry of five protoplanetary disks observed with near-infrared imaging polarimetry using Subaru-HiCIAO. Using as inputs the observed distribution of polarized intensity (PI), disk inclination, assumed properties for dust scattering, and other reasonable approximations, we calculate a differential equation to derive the surface geometry. This equation is numerically integrated along the distance from the star at a given position angle. We show that, using these approximations, the local maxima in the PI distribution of spiral arms (SAO 206462, MWC 758) and rings (2MASS J16042165-2130284, PDS 70) are associated with local concave-up structures on the disk surface. We also show that the observed presence of an inner gap in scattered light still allows the possibility of a disk surface that is parallel to the light path from the star, or a disk that is shadowed by structures in the inner radii. Our analysis for rings does not show the presence of a vertical inner wall as often assumed in studies of disks with an inner gap. Finally, we summarize the implications of spiral and ring structures as potential signatures of ongoing planet formation.

• OSTI ID: 22370299
• Journal Information: Astrophysical Journal, Vol. 795, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
APPROXIMATIONS
DIFFERENTIAL EQUATIONS
DISTANCE
DISTRIBUTION
INCLINATION
NEAR INFRARED RADIATION
PLANETS
POLARIMETRY
POLARIZATION
PROTOPLANETS
SCATTERING
STARS
VISIBLE RADIATION