Time-variable accretion in the TW Hya star/disk system

J. A. Eisner; G. W. Doppmann; J. R. Najita; D. McCarthy; C. Kulesa; B. J. Swift; J. Teske

doi:10.1088/2041-8205/722/1/L28

Time-variable accretion in the TW Hya star/disk system

J. A. Eisner, G. W. Doppmann, J. R. Najita, D. McCarthy, C. Kulesa, B. J. Swift, J. Teske

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13 Scopus citations

Abstract

We present two epochs of observations of TW Hya from the high-dispersion near-IR spectrograph ARIES at the Multiple Mirror Telescope.We detect strong emission from the Brγ transition of hydrogen, indicating an accretion rate substantially larger than previously estimated, using hydrogen line emission. The Brγ line strength varies across our two observed epochs.We alsomeasure circumstellar-to-stellar flux ratios (i.e., veilings) that appear close to zero in both epochs. These findings suggest that TW Hya experiences episodes of enhanced accretion while the inner disk remains largely devoid of dust. We discuss several physical mechanisms that may explain these observations.

Original language	English (US)
Pages (from-to)	L28-L32
Journal	Astrophysical Journal Letters
Volume	722
Issue number	1 PART 2
DOIs	https://doi.org/10.1088/2041-8205/722/1/L28
State	Published - Oct 10 2010

Keywords

Planetary systems
Stars: individual (TW Hya)
Stars: pre-main sequence
Techniques: spectroscopic

ASJC Scopus subject areas

Astronomy and Astrophysics
Space and Planetary Science

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10.1088/2041-8205/722/1/L28

Cite this

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title = "Time-variable accretion in the TW Hya star/disk system",

abstract = "We present two epochs of observations of TW Hya from the high-dispersion near-IR spectrograph ARIES at the Multiple Mirror Telescope.We detect strong emission from the Brγ transition of hydrogen, indicating an accretion rate substantially larger than previously estimated, using hydrogen line emission. The Brγ line strength varies across our two observed epochs.We alsomeasure circumstellar-to-stellar flux ratios (i.e., veilings) that appear close to zero in both epochs. These findings suggest that TW Hya experiences episodes of enhanced accretion while the inner disk remains largely devoid of dust. We discuss several physical mechanisms that may explain these observations.",

keywords = "Planetary systems, Stars: individual (TW Hya), Stars: pre-main sequence, Techniques: spectroscopic",

author = "Eisner, {J. A.} and Doppmann, {G. W.} and Najita, {J. R.} and D. McCarthy and C. Kulesa and Swift, {B. J.} and J. Teske",

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language = "English (US)",

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TY - JOUR

T1 - Time-variable accretion in the TW Hya star/disk system

AU - Eisner, J. A.

AU - Doppmann, G. W.

AU - Najita, J. R.

AU - McCarthy, D.

AU - Kulesa, C.

AU - Swift, B. J.

AU - Teske, J.

PY - 2010/10/10

Y1 - 2010/10/10

N2 - We present two epochs of observations of TW Hya from the high-dispersion near-IR spectrograph ARIES at the Multiple Mirror Telescope.We detect strong emission from the Brγ transition of hydrogen, indicating an accretion rate substantially larger than previously estimated, using hydrogen line emission. The Brγ line strength varies across our two observed epochs.We alsomeasure circumstellar-to-stellar flux ratios (i.e., veilings) that appear close to zero in both epochs. These findings suggest that TW Hya experiences episodes of enhanced accretion while the inner disk remains largely devoid of dust. We discuss several physical mechanisms that may explain these observations.

AB - We present two epochs of observations of TW Hya from the high-dispersion near-IR spectrograph ARIES at the Multiple Mirror Telescope.We detect strong emission from the Brγ transition of hydrogen, indicating an accretion rate substantially larger than previously estimated, using hydrogen line emission. The Brγ line strength varies across our two observed epochs.We alsomeasure circumstellar-to-stellar flux ratios (i.e., veilings) that appear close to zero in both epochs. These findings suggest that TW Hya experiences episodes of enhanced accretion while the inner disk remains largely devoid of dust. We discuss several physical mechanisms that may explain these observations.

KW - Planetary systems

KW - Stars: individual (TW Hya)

KW - Stars: pre-main sequence

KW - Techniques: spectroscopic

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VL - 722

SP - L28-L32

JO - Astrophysical Journal Letters

JF - Astrophysical Journal Letters

IS - 1 PART 2

ER -

Time-variable accretion in the TW Hya star/disk system

Abstract

Keywords

ASJC Scopus subject areas

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