SIMBAD references

2002ApJ...567..434K - Astrophys. J., 567, 434-440 (2002/March-1)

Evidence for accretion: high-resolution X-ray spectroscopy of the classical T Tauri star TW Hydrae.


Abstract (from CDS):

We present high-resolution X-ray spectra of the X-ray-bright classical T Tauri star, TW Hydrae, covering the wavelength range of 1.5-25 Å. The differential emission measure derived from fluxes of temperature-sensitive emission lines shows a plasma with a sharply peaked temperature distribution, peaking at log T=6.5. Abundance anomalies are apparent, with iron very deficient relative to oxygen, while neon is enhanced relative to oxygen. Density-sensitive line ratios of Ne IX and O VII indicate densities near log ne=13. A flare with rapid (∼1 ks) rise time was detected during our 48 ks observation; however, based on analysis of the emission-line spectrum during quiescent and flaring states, the derived plasma parameters do not seem strongly time-dependent. The inferred plasma temperature distribution and densities are consistent with a model in which the bulk of the X-ray emission from TW Hya is generated via mass accretion from its circumstellar disk. Assuming that accretion powers the X-ray emission, our results for log ne suggest an accretion rate of ∼10–8 M yr–1.

Abstract Copyright:

Journal keyword(s): Stars: Circumstellar Matter - Stars: Formation - Stars: Individual: Constellation Name: TW Hydrae - X-Rays: Stars

Simbad objects: 11

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2002ApJ...567..434K and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact