Dust and Polycyclic Aromatic Hydrocarbon in the Pre-Transitional Disk around HD 169142

By Keith Cowing
Press Release
February 4, 2016
Filed under ,
Dust and Polycyclic Aromatic Hydrocarbon in the Pre-Transitional Disk around HD 169142

The pre-transitional disk around the Herbig Ae star HD 169142 shows a complex structure of possible ongoing planet formation in dust thermal emission from the near infrared (IR) to millimeter wavelength range.

Also, a distinct set of broad emission features at 3.3, 6.2, 7.7, 8.6, 11.3, and 12.7 μm, commonly attributed to polycyclic aromatic hydrocarbons (PAHs), are detected prominently in the HD 169142 disk. We model the spectral energy distribution (SED) as well as the PAH emission features of the HD 169142 disk simultaneously with porous dust and astronomical-PAHs taking into account the spatially resolved disk structure. Our porous dust model consisting of three distinct components that are primarily concentrated in the inner ring, middle ring, and outer disk, respectively, provides an excellent fit to the entire SED, and the PAH model closely reproduces the observed PAH features.

The accretion of ice mantles onto porous dust aggregates occurs between ~16 AU and 60 AU, which overlaps with the spatial extent (~50 AU) of the observed PAH emission features. Finally, we discuss the role of PAHs in the formation of planets possibly taking place in the HD 169142 system.

Ji Yeon Seok, Aigen Li
(Submitted on 15 Dec 2015)

Comments: 35 pages, 8 figures, 2 tables, accepted for publication in ApJ
Subjects: Solar and Stellar Astrophysics (astro-ph.SR)
Cite as: arXiv:1512.04992 [astro-ph.SR] (or arXiv:1512.04992v1 [astro-ph.SR] for this version)
Submission history
From: Ji Yeon Seok
[v1] Tue, 15 Dec 2015 22:26:55 GMT (421kb)

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻