THE STRUCTURE OF PRE-TRANSITIONAL PROTOPLANETARY DISKS. I. RADIATIVE TRANSFER MODELING OF THE DISK+CAVITY IN THE PDS 70 SYSTEM

Journal Article · Sat Dec 01 04:00:00 EST 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/760/2/111· OSTI ID:22086248

Ruobing, Dong; Rafikov, Roman; Zhaohuan, Zhu; Brandt, Timothy ^[1]; Hashimoto, Jun ^[2]; Whitney, Barbara ^[3]; Kudo, Tomoyuki; Egner, S; Guyon, O; Hayano, Y ^[4]; Muto, Takayuki ^[5]; McClure, Melissa K ^[6]; Wisniewski, John ^[7]; Abe, L ^[8]; Brandner, W; Feldt, M; Goto, M ^[9]; Carson, J ^[10]; Grady, C ^[11]; Hayashi, M ^[12] ; others, and

---

1. Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)
2. National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
3. Astronomy Department, University of Wisconsin-Madison, 475 N. Charter St., Madison, WI 53706 (United States)
4. Subaru Telescope, 650 North A'ohoku Place, Hilo, HI 96720 (United States)
5. Division of Liberal Arts, Kogakuin University, 1-24-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo 163-8677 (Japan)
6. Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48105 (United States)
7. HL Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W Brooks St, Norman, OK 73019 (United States)
8. Laboratoire Lagrange, UMR7293, Universite de Nice-Sophia Antipolis, CNRS, Observatoire de la Cote d'Azur, F-06300 Nice (France)
9. Max Planck Institute for Astronomy, Heidelberg (Germany)
10. Department of Physics and Astronomy, College of Charleston, 58 Coming St., Charleston, SC 29424 (United States)
11. ExoPlanets and Stellar Astrophysics Laboratory, Code 667, Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
12. Department of Astronomy, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan)

Through detailed radiative transfer modeling, we present a disk+cavity model to simultaneously explain both the spectral energy distribution (SED) and Subaru H-band polarized light imaging for the pre-transitional protoplanetary disk PDS 70. In particular, we are able to match not only the radial dependence but also the absolute scale of the surface brightness of the scattered light. Our disk model has a cavity 65 AU in radius, which is heavily depleted of sub-micron-sized dust grains, and a small residual inner disk that produces a weak but still optically thick near-IR excess in the SED. To explain the contrast of the cavity's edge in the Subaru image, a factor of {approx}1000 depletion for the sub-micron-sized dust inside the cavity is required. The total dust mass of the disk may be on the order of 10{sup -4} M {sub Sun }, only weakly constrained due to the lack of long-wavelength observations and the uncertainties in the dust model. The scale height of the sub-micron-sized dust is {approx}6 AU at the cavity edge, and the cavity wall is optically thick in the vertical direction at H-band. PDS 70 is not a member of the class of (pre-)transitional disks identified by Dong et al., whose members only show evidence of the cavity in the millimeter-size dust but not the sub-micron-sized dust in resolved images. The two classes of (pre-)transitional disks may form through different mechanisms, or they may simply be at different evolution stages in the disk-clearing process.

• OSTI ID: 22086248
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 760; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ASTRONOMY
ASTROPHYSICS
BRIGHTNESS
COMPUTERIZED SIMULATION
COSMIC DUST
ENERGY SPECTRA
IMAGES
INTERSTELLAR GRAINS
MAIN SEQUENCE STARS
MASS
PROTOPLANETS
RADIANT HEAT TRANSFER
SCALE HEIGHT
STAR EVOLUTION
VISIBLE RADIATION