A Panchromatic View of Brown Dwarf Aurorae

@article{Pineda2017APV,
  title={A Panchromatic View of Brown Dwarf Aurorae},
  author={J. Sebastian Pineda and Gregg Hallinan and Melodie M. Kao},
  journal={arXiv: Solar and Stellar Astrophysics},
  year={2017}
}
Stellar coronal activity has been shown to persist into the low-mass star regime, down to late M-dwarf spectral types. However, there is now an accumulation of evidence suggesting that at the end of the main sequence there is a transition in the nature of the magnetic activity from chromospheric and coronal to planet-like and auroral, from local impulsive heating via flares and MHD wave dissipation to energy dissipation from strong large-scale magnetospheric current systems. We examine this… Expand
Environmental effects on the ionization of brown dwarf atmospheres
Brown dwarfs emit bursts of Halpha, white light flares, and show radio flares and quiescent radio emission. They are suggested to form Aurorae, similar to planets in the solar system but much moreExpand
ASKAP detection of periodic and elliptically polarized radio pulses from UV Ceti
Active M dwarfs are known to produce bursty radio emission, and multiwavelength studies have shown that solar-like magnetic activity occurs in these stars. However, coherent bursts from active MExpand
Detection of α Centauri at radio wavelengths: chromospheric emission and search for star-planet interaction
At radio wavelengths, solar type stars emit thermal free-free and gyroresonance, gyrosynchrotron, and impulsive coherent emission. Thermal free-free emission originates at layers where the opticalExpand
A Deep Radio Limit for the TRAPPIST-1 System
The first nearby very-low-mass star–planet-host discovered, TRAPPIST-1, presents not only a unique opportunity for studying a system of multiple terrestrial planets, but a means to probeExpand
The UV Spectrum of the Ultracool Dwarf LSR J1835+3259 Observed with the Hubble Space Telescope
An interesting question about ultracool dwarfs recently raised in the literature is whether their emission is purely internally driven or partially powered by external processes similar to planetaryExpand
Unlocking the Origins of Ultracool Dwarf Radio Emission
Empirical trends in stellar X-ray and radio luminosities suggest that low-mass ultracool dwarfs (UCDs) should not produce significant radio emission. Defying these expectations, strong nonthermalExpand
The Polarization Mode of the Auroral Radio Emission from the Early-Type Star HD 142301
We report the detection of the auroral radio emission from the early-type magnetic star HD142301. New VLA observations of HD142301 detected highly polarized amplified emission occurring at fixedExpand
Constraints on magnetospheric radio emission from Y dwarfs
As a pilot study of magnetism in Y dwarfs, we have observed the three known infrared variable Y dwarfs WISE J085510.83−071442.5, WISE J140518.40+553421.4, and WISEP J173835.53+273258.9 with theExpand
The Strongest Magnetic Fields on the Coolest Brown Dwarfs
We have used NSF's Karl G. Jansky Very Large Array to observe a sample of five known radio-emitting late-L and T dwarfs ranging in age from ~0.2 to 3.4 Gyr. We observed each target for seven hours,Expand
A Stacking Search for Gamma-Ray Emission from Nearby Flare Stars and the Periodic Source TVLM 513-46546
So far, the Sun is the only isolated main sequence star detected in gamma-rays, particularly during powerful flares. Young ultracool dwarfs are far more active so they are also plausible gamma-rayExpand
...
1
2
3
...

References

SHOWING 1-10 OF 205 REFERENCES
Magnetospherically driven optical and radio aurorae at the end of the stellar main sequence
TLDR
Radio and optical spectroscopic observations of an object at the end of the stellar main sequence, located right at the boundary between stars and brown dwarfs, are reported, from which radio and optical auroral emissions both powered by magnetospheric currents are detected. Expand
A Survey for Hα Emission from Late L Dwarfs and T Dwarfs
Recently, studies of brown dwarfs have demonstrated that they possess strong magnetic fields and have the potential to produce radio and optical auroral emissions powered by magnetospheric currents.Expand
ON A TRANSITION FROM SOLAR-LIKE CORONAE TO ROTATION-DOMINATED JOVIAN-LIKE MAGNETOSPHERES IN ULTRACOOL MAIN-SEQUENCE STARS
For main-sequence stars beyond spectral type M5, the characteristics of magnetic activity common to warmer solar-like stars change into the brown-dwarf domain: the surface magnetic field becomes moreExpand
TRENDS IN ULTRACOOL DWARF MAGNETISM. I. X-RAY SUPPRESSION AND RADIO ENHANCEMENT
Although ultracool dwarfs (UCDs) are now known to generate and dissipate strong magnetic fields, a clear understanding of the underlying dynamo is still lacking. We have performed X-ray and radioExpand
Discovery of radio emission from the brown dwarf LP944-20
TLDR
It is shown that LP944-20 has an unusually weak magnetic field in comparison to active M-dwarf stars, which might explain the previous null optical and X-rays results, as well as the strength of the radio emissions compared to those at X-ray wavelengths. Expand
3D modelling of stellar auroral radio emission
The electron cyclotron maser is the coherent emission process that gives rise to the radio lighthouse effect observed in the hot magnetic chemically peculiar star CU Virginis. It has also beenExpand
Modelling the radio pulses of an ultracool dwarf
Context. Recently, unanticipated magnetic activity in ultracool dwarfs (UCDs, spectral classes later than M7) has emerged from a number of radio observations. The highly (up to 100%) circularlyExpand
THE FIRST MILLIMETER DETECTION OF A NON-ACCRETING ULTRACOOL DWARF
The well-studied M9 dwarf TVLM513–46546 is a rapid rotator (P 2 rot ~ hr) hosting a stable, dipolar magnetic field of ∼3 kG surface strength. Here we report its detection with ALMA at 95 GHz at aExpand
Large-scale magnetic topologies of early M dwarfs
We present here additional results of a spectropolarimetric survey of a small sample of stars ranging from spectral type M0 to M8 aimed at investigating observationally how dynamo processes operateExpand
Auroral radio emissions at the outer planets: Observations and theories
We review both observational and theoretical aspects of the generation of auroral radio emissions at the outer planets, trying to organize the former in a coherent frame set by the latter. ImportantExpand
...
1
2
3
4
5
...