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

Joshua A Eisner, G. W. Doppmann, J. R. Najita, Donald W Mccarthy, C. Kulesa, B. J. Swift, J. Teske

Research output: Contribution to journalArticle

12 Citations (Scopus)

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 languageEnglish (US)
JournalAstrophysical Journal Letters
Volume722
Issue number1 PART 2
DOIs
StatePublished - Oct 10 2010

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accretion
time measurement
hydrogen
stars
dust
spectrographs
telescopes
mirrors
rate

Keywords

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

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Time-variable accretion in the TW Hya star/disk system. / Eisner, Joshua A; Doppmann, G. W.; Najita, J. R.; Mccarthy, Donald W; Kulesa, C.; Swift, B. J.; Teske, J.

In: Astrophysical Journal Letters, Vol. 722, No. 1 PART 2, 10.10.2010.

Research output: Contribution to journalArticle

Eisner, Joshua A ; Doppmann, G. W. ; Najita, J. R. ; Mccarthy, Donald W ; Kulesa, C. ; Swift, B. J. ; Teske, J. / Time-variable accretion in the TW Hya star/disk system. In: Astrophysical Journal Letters. 2010 ; Vol. 722, No. 1 PART 2.
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AU - Doppmann, G. W.

AU - Najita, J. R.

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AU - Kulesa, C.

AU - Swift, B. J.

AU - Teske, J.

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