Emission lines in the atmosphere of the irradiated brown dwarf WD0137-349B

Abstract

We present new optical and near-infrared spectra of WD0137-349; a close white dwarf - brown dwarf non-interacting binary system with a period of $\approx$114 minutes. We have confirmed the presence of H$\alpha$ emission and discovered He, Na, Mg, Si, K, Ca, Ti, and Fe emission lines originating from the brown dwarf atmosphere. This is the first brown dwarf atmosphere to have been observed to exhibit metal emission lines as a direct result of intense irradiation. The equivalent widths of many of these lines show a significant difference between the day and night sides of the brown dwarf. This is likely an indication that efficient heat redistribution may not be happening on this object, in agreement with models of hot Jupiter atmospheres. The H$\alpha$ line strength variation shows a strong phase dependency as does the width. We have simulated the Ca II emission lines using a model that includes the brown dwarf Roche geometry and limb darkening and we estimate the mass ratio of the system to be 0.135$\pm$0.004. We also apply a gas-phase equilibrium code using a prescribed drift-phoenix model to examine how the chemical composition of the brown dwarf upper atmosphere would change given an outward temperature increase, and discuss the possibility that this would induce a chromosphere above the brown dwarf atmosphere.

arXiv comment10 pages, 7 figures, 2 tables

References in corpus (46)

• X-shooter, the new wide band intermediate resolution spectrograph at the ESO Very Large Telescope
• An Infrared Spectroscopic Sequence of M, L and T Dwarfs
• The Deuterium-Burning Mass Limit for Brown Dwarfs and Giant Planets
• On the Cool Side: Modeling the Atmospheres of Brown Dwarfs and Giant Planets
• Doppler Signatures of the Atmospheric Circulation on Hot Jupiters
• Survival of a brown dwarf after engulfment by a red giant star
• Dynamic mineral clouds on HD 189733b I. 3D RHD with kinetic, non-equilibrium cloud formation
• Debris Disks Around White Dwarfs: The DAZ Connection
• 2MASSJ035523.51+113337.4: A Young, Dusty, Nearby, Isolated Brown Dwarf Resembling A Giant Exoplanet
• The Spectrum of the Brown Dwarf Gliese 229B
• The Effects of Irradiation on Hot Jovian Atmospheres: Heat Redistribution and Energy Dissipation
• DA white dwarfs in SDSS DR7 and a search for infrared excess emission
• Precise mass and radius values for the white dwarf and low mass M dwarf in the pre-cataclysmic binary NN Serpentis
• The WIRED Survey II: Infrared Excesses in the SDSS DR7 White Dwarf Catalog
• The chemical diversity of exo-terrestrial planetary debris around white dwarfs
• BOSS Ultracool Dwarfs I: Colors and Magnetic Activity of M and L dwarfs
• The mineral clouds on HD 209458b and HD189733b
• A Possible Brown Dwarf Companion to the White Dwarf GD1400
• Atmospheres of Brown Dwarfs
• White dwarfs in the UKIDSS Large Area Survey: The Substellar Companion Fraction
• A Survey for H-alpha Emission from Late L dwarfs and T dwarfs
• Modelling the local and global cloud formation on HD 189733b
• The Formation of Cataclysmic Variables with Brown Dwarf Secondaries
• NLTT5306: The shortest Period Detached White Dwarf + Brown Dwarf Binary
• Two white dwarfs in ultrashort binaries with detached, eclipsing, likely substellar companions detected by K2
• The substellar companion in the eclipsing white dwarf binary SDSS J141126.20+200911.1
• Multiwaveband photometry of the irradiated brown dwarf WD0137-349B
• The nature of the close magnetic white dwarf + probable brown dwarf binary SDSS J121209.31+013627.7
• PHOENIX model chromospheres of mid- to late-type M dwarfs
• An irradiated brown-dwarf companion to an accreting white dwarf
• WD0837+185:the formation and evolution of an extreme mass ratio white dwarf-brown dwarf binary in Praesepe
• Model Atmospheres for Irradiated Stars in pre-Cataclysmic Variables
• A Signature of Chromospheric Activity in Brown Dwarfs Revealed by 2.5-5.0 Micron AKARI Spectra
• The mass and radius of the M dwarf companion to GD 448
• Reference study to characterise plasma and magnetic properties of ultra-cool atmospheres
• The Hyperactive L Dwarf 2MASS J13153094-2649513: Continued Emission and a Brown Dwarf Companion
• The eclipsing post-common envelope binary CSS21055: a white dwarf with a probable brown-dwarf companion
• The pre-cataclysmic variable, LTT560
• On the evidence for brown-dwarf secondary stars in cataclysmic variables
• Small hydrocarbon molecules in cloud-forming Brown Dwarf and giant gas planet atmospheres
• The Metallicity of Stars with Close Companions
• Accretion in the detached post-common-envelope binary LTT 560
• A new L5 brown dwarf member of the Hyades cluster with chromospheric activity
• A near-IR spectrum of the DO white dwarf RE J0503-285
• Brown Dwarf Companions to White Dwarfs
• Mechanical energy fluxes associated with saturated coronal heating in M dwarfs: comparison with predictions of a turbulent dynamo

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