A Far-ultraviolet Atlas of Low-resolution Hubble Space Telescope Spectra of T Tauri Stars

Дата и время публикации : 2012-05-22T02:37:26Z

Авторы публикации и институты :
Hao Yang
Gregory J. Herczeg
Jeffrey L. Linsky
Alexander Brown
Christopher M. Johns-Krull
Laura Ingleby
Nuria Calvet
Edwin Bergin
Jeff A. Valenti

Ссылка на журнал-издание: ApJ, 2012, 744, 121
Коментарии к cтатье: 89 pages, 30 figures, published in ApJ
Первичная категория: astro-ph.SR

Все категории : astro-ph.SR, astro-ph.EP

Краткий обзор статьи: We present a far-ultraviolet (FUV) spectral atlas consisting of spectra of 91 pre-main sequence stars. Most stars in this sample were observed with the Space Telescope Imaging Spectrograph (STIS) and Advanced Camera for Surveys (ACS) on the emph{Hubble Space Telescope} (emph{HST}). We find strong correlations among the ion{O}{1} $lambda$1304 triplet, %ion{C}{2} $lambda$1335, the ion{Si}{4} $lambdalambda$1394/1403 doublet, the ion{C}{4} $lambda$1549 doublet, and the ion{He}{2} $lambda$1640 line luminosities. For classical T Tauri stars (CTTSs), we also find strong correlations between these lines and the accretion luminosity, suggesting that these lines form in processes related to accretion. These FUV line fluxes and X-ray luminosity correlate loosely with large scatters. The FUV emission also correlates well with H$alpha$, H$beta$, and ion{Ca}{2} K line luminosities. These correlations between FUV and optical diagostics can be used to obtain rough estimates of FUV line fluxes from optical observations. Molecular hydrogen (H$_{2}$) emission is generally present in the spectra of actively accreting CTTSs but not the weak-lined T Tauri stars (WTTSs) that are not accreting. The presence of H$_2$ emission in the spectrum of HD 98800 N suggests that the disk should be classified as actively accreting rather than a debris disk. The spectra in the atlas are available at http://archive.stsci.edu/prepds/ttauriatlas.

Category: Physics