A large X-ray flare from the Herbig Ae star V892 Tau

Abstract

We report the XMM-Newton observation of a large X-ray flare from the Herbig Ae star V892 Tau. The apparent low mass companion of V892 Tau, V892 Tau NE, is unresolved by XMM-Newton. Nevertheless there is compelling evidence from combined XMM-Newton and Chandra data that the origin of the flare is the Herbig Ae star V892 Tau. During the flare the X-ray luminosity of V892 Tau increases by a factor of ~15, while the temperature of the plasma increases from kT ~ 1.5 keV to kT ~ 8 keV. From the scaling of the flare event, based on hydrodynamic modeling, we conclude that a 500 G magnetic field is needed in order to confine the plasma. Under the assumptions that a dynamo mechanism is required to generate such a confining magnetic field and that surface convection is a necessary ingredient for a dynamo, our findings provide indirect evidence for the existence of a significant convection zone in the stellar envelope of Herbig Ae stars.

accepted for publication in A&A (12 pages - 6 figures)

References in corpus (2)

• An XMM-Newton-based X-ray survey of pre-main sequence stellar emission in the L1551 star-forming complex
• The Flight Spectral Response of the ACIS Instrument

Cited by in corpus (23)

• X-Ray Spectroscopy of Stars
• X-ray flares in Orion young stars. I. Flare characteristics
• Diagnostics of stellar flares from X-ray observations: from the decay to the rise phase
• On the origin of the X-ray emission from Herbig Ae/Be stars
• The first high-resolution X-ray spectrum of a Herbig Star: The case of AB Aurigae
• The Herbig Ae star HD 163296 in X-rays
• The Gould Belt Very Large Array Survey IV: The Taurus-Auriga complex
• Jets, accretion, coronae and all that: The enigmatic X-rays from the Herbig star HD 163296
• Close binary companions of the HAeBe stars LkHa 198, Elias 1, HK Ori and V380 Ori
• Further X-ray detections of Herbig stars
• XMM-Newton X-ray study of early type stars in the Carina OB1 association
• Spatially Resolved 3 micron Spectroscopy of Elias 1: Origin of Diamonds in Protoplanetary Disks
• New Perspectives on the X-ray Emission of HD 104237 and Other Nearby Herbig Ae/Be Stars from XMM-Newton and Chandra
• Spectral properties of X-ray bright variable sources in the Taurus Molecular Cloud
• An XMM-Newton view of the young open cluster NGC 6231 III. Optically faint X-ray sources
• L1495 Revisited: A PPMAP View of a Star-Forming Filament
• On the origin of the X-ray emission towards the early Herbig Be star MWC 297
• Chandra observations of the massive star-forming region S106: X-ray emission from the embedded massive protostellar object IRS 4
• A detailed study of the rise phase of a long duration X-ray flare in the young star TWA 11B
• Tetrahedral hydrocarbon nanoparticles in space: X-ray spectra
• Diamonds and PAHs in the Circumstellar Environment of the Herbig Ae/Be Star Elias 1
• Accretion, jets and winds: High-energy emission from young stellar objects
• Probing dust and grain growth in the optically thick circumbinary ring of V892 Tau