Inner Warm Disk of ESO Hα 279a Revealed by NA i and CO Overtone Emission Lines

Journal Article · Thu Jul 20 04:00:00 EDT 2017 · Astrophysical Journal

DOI:https://doi.org/10.3847/1538-4357/AA799E· OSTI ID:22876017

Lyo, A-Ran; Kim, Jongsoo; Lee, Jae-Joon; Kim, Kyoung-Hee; Kang, Jihyun; Byun, Do-Young; Park, Chan; Chun, Moo-Young; Oh, Heeyoung; Yu, Young Sam; Oh, Jae Sok; Jeong, Ueejeong; Hwang, Narae; Park, Byeong-Gon; Lee, Sungho ^[1]; Mace, Gregory; Sokal, Kimberly R.; Kaplan, Kyle ^[2]; Kim, Hwihyun ^[3]; Pak, Soojong ^[4] ; others, and

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1. Korea Astronomy and Space Science Institute, 776 Daedeokdae-ro, Yuseong-gu, Daejeon 34055 (Korea, Republic of)
2. Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States)
3. Gemini Observatory, Southern Operations Center, c/o AURA, Casilla 603, La Serena (Chile)
4. School of Space Research and Institute of Natural Sciences, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin-si, Gyeonggi-do 17104 (Korea, Republic of)

We present an analysis of near-infrared, high-resolution spectroscopy toward the flat-spectrum young stellar object (YSO) ESO Hα 279a (∼1.5M {sub ⊙}) in the Serpens star-forming region at a distance of 429 pc. Using the Immersion GRating INfrared Spectrometer (IGRINS; R ≈ 45,000), we detect emission lines originating from the accretion channel flow, jet, and inner disk. Specifically, we identify hydrogen Brackett series recombination, [Fe ii], [Fe iii], [Fe iv], Ca i, Na i, H{sub 2}, H{sub 2}O, and CO overtone emission lines. By modeling five bands of CO overtone emission lines and the symmetric double-peaked line profile for Na i emission lines, we find that ESO Hα 279a has an actively accreting Keplerian disk. From our Keplerian disk model, we find that Na i emission lines originate between 0.04 and 1.00 au, while the CO overtone emission lines are from the outer part of the disk, in the range between 0.22 and 3.00 au. The model reveals that the neutral atomic Na gas is a good tracer of the innermost region of the actively accreting disk. We derive a mass accretion rate of 2--10×10{sup −7} M {sub ⊙} yr{sup −1} from the measured Brγ emission luminosity of 1.78(±0.31) × 10{sup 31} erg s{sup −1}.

• OSTI ID: 22876017
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 844; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
CALCIUM
CARBON MONOXIDE
COMPUTERIZED SIMULATION
DISTANCE
EMISSION
HYDROGEN
INFRARED SPECTROMETERS
IRON
LUMINOSITY
MASS
PROTOPLANETS
PROTOSTARS
RECOMBINATION
SODIUM
SPECTRA
STARS
SYMMETRY
WATER