Chandra X-ray Observations of V830 Tau: A T Tauri Star Hosting an Evanescent Planet

Abstract

A radial velocity study by Donati et al. (2016) reported the detection of a close-in giant planet in a 4.93 d orbit around the ~2 Myr old weak-lined T Tauri star V830 Tau. Because of the stringent timescale constraints that a very young host star like V830 Tau would place on hot Jupiter formation models and inward migration mechanisms, independent confirmation of the planet's existence is needed but so far has not been obtained. We present new Chandra X-ray observations of V830 Tau. The Chandra observations in combination with previous XMM-Newton observations reveal strong variable X-ray emission with an X-ray luminosity spanning the range log Lx = 30.10 - 30.87 ergs/s. Chandra High Energy Transmission Grating (HETG) spectra show emission lines formed over a range of plasma temperatures from ~4 MK (Ne IX) to ~16 MK (S XV). At the separation of the reported planet (0.057 au) the X-ray flux is ~10${}^6$ - 10${}^7$ times greater than the Sun's X-ray flux at Jupiter. We provide estimates of the X-ray ionization and atmospheric heating rates at the planet's separation and identify areas of uncertainty that will need to be addressed in any future atmospheric models.

arXiv comment21 pages, 6 figures

References in corpus (38)

• Collisional Plasma Models with APEC/APED: Emission Line Diagnostics of Hydrogen-like and Helium-like Ions
• Detection of an Extrasolar Planet Atmosphere
• Evolution of the Solar Activity over Time and Effects on Planetary Atmospheres: I. High-energy Irradiances (1-1700 A)
• Atmospheric Escape from Hot Jupiters
• Origins of Hot Jupiters
• An Optical Spectroscopic Study of T Tauri Stars. I. Photospheric Properties
• Planetary evaporation by UV & X-ray radiation: basic hydrodynamics
• Estimation of the XUV radiation onto close planets and their evaporation
• The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST)
• Albedo and Reflection Spectra of Extrasolar Giant Planets
• Photometric Light Curves and Polarization of Close-in Extrasolar Giant Planets
• LkCa 15: A Young Exoplanet Caught at Formation?
• Accreting Protoplanets in the LkCa 15 Transition Disk
• Theoretical Spectra and Atmospheres of Extrasolar Giant Planets
• Determination of the gas-to-dust ratio in nearby dense clouds using X-ray absorption measurements
• Simulating the escaping atmospheres of hot gas planets in the solar neighborhood
• Heating and Ionization of X-Winds
• X-ray Emission from T Tauri Stars and the Role of Accretion: Inferences from the XMM-Newton Extended Survey of the Taurus Molecular Cloud
• A hot Jupiter orbiting a 2-Myr-old solar-mass T Tauri star
• Coronal properties of planet-bearing stars
• Results of the ROTOR-program. II. The long-term photometric variability of weak-line T Tauri stars
• X-ray flares in Orion young stars. I. Flare characteristics
• HD 209458: Physical Parameters of the Parent Star and the Transiting Planet
• Computing Intrinsic Lyman-alpha Fluxes of F5 V to M5 V Stars
• Cosmic-ray and X-ray Heating of Interstellar Clouds and Protoplanetary Disks
• A hot Jupiter around the very active weak-line T Tauri star TAP 26
• The upper atmosphere of the exoplanet HD209458b revealed by the sodium D lines: Temperature-pressure profile, ionization layer, and thermosphere
• Chemical Modelling of Young Stellar Objects, I. Method and Benchmarks
• Keck Interferometer observations of classical and weak line T Tauri stars
• A Systematic Study of X-Ray Flares from Low-Mass Young Stellar Objects in the Rho Ophiuchi Star-Forming Region with Chandra
• Magnetic activity and hot Jupiters of young Suns: the weak-line T Tauri stars V819 Tau and V830 Tau
• The hot Jupiter of the magnetically-active weak-line T Tauri star V830 Tau
• The fate of close-in planets: tidal or magnetic migration?
• Spectral properties of X-ray bright variable sources in the Taurus Molecular Cloud
• The GAPS Programme at TNG XXVII. Reassessment of a young planetary system with HARPS-N: is the hot Jupiter V830 Tau b really there?
• X-ray Irradiation of the LkCa 15 Protoplanetary Disk
• Variable Radio Emission from the Young Stellar Host of a Hot Jupiter
• XMM-Newton X-ray Observations of LkCa 15: A T Tauri Star With a Formative Planetary System