312 citations · 2k across the 45 of their papers we have counts for
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A Semi-Empirical Estimate of Solar EUV Evolution from 10 Myr to 10 Gyr
Kevin France, Girish Duvvuri, Cynthia Froning +9
The extreme-ultraviolet (EUV; 100 -- 911 Å) spectra of F, G, K, and M stars provide diagnostics of the stellar chromosphere through the corona, with line and continuum formation te…
Binarity Enhances the Occurrence Rate of Radiation Belt Emissions in Ultracool Dwarfs
Melodie M. Kao, J. Sebastian Pineda
Despite a burgeoning set of ultracool dwarf (M7) radio detections, their radio emissions remain enigmatic. Open questions include the plasma source and acceleration mechanism…
Impact of Electron Precipitation on Brown Dwarf Atmospheres and the Missing Auroral H Emission
J. Sebastian Pineda, Gregg Hallinan, Jean Michel Desert +1
Recent observations have demonstrated that very-low mass stars and brown dwarfs are capable of sustaining strong magnetic fields despite their cool and neutral atmospheres. These k…
The High-Energy Spectrum of the Young Planet Host V1298 Tau
Girish M. Duvvuri, P. Wilson Cauley, Fernando Cruz Aguirre +4
V1298 Tau is a young pre-main sequence star hosting four known exoplanets that are prime targets for transmission spectroscopy with current-generation instruments. This work pieces…
Measurement of stellar and substellar winds using white dwarf hosts
N. Walters, J. Farihi, P. Dufour +2
White dwarfs stars are known to be polluted by their active planetary systems, but little attention has been paid to the accretion of wind from low-mass companions. The capture of…
The MUSCLES Extension for Atmospheric and Transmission Spectroscopy: UV and X-ray Host-star Observations for JWST ERS & GTO Targets
Patrick R. Behr, Kevin France, Alexander Brown +8
X-ray through infrared spectral energy distributions (SEDs) are essential for understanding a star's effect on exoplanet atmospheric composition and evolution. We present a catalog…
The winds of young Solar-type stars in the Pleiades, AB Doradus, Columba and Pictoris
Dag Evensberget, Stephen C. Marsden, Bradley D. Carter +6
Solar-type stars, which shed angular momentum via magnetised stellar winds, enter the main sequence with a wide range of rotational periods . This initially wide rang…
Coherent radio bursts from known M-dwarf planet host YZ Ceti
J. Sebastian Pineda, Jackie Villadsen
Observing magnetic star-planet interactions (SPI) offers promise for determining magnetic fields of exoplanets. Models of sub-Alfvénic SPI predict that terrestrial planets in close…
Coronal X-Ray Emission from Nearby, Low-Mass, Exoplanet Host Stars Observed by the MUSCLES and Mega-MUSCLES HST Treasury Survey Projects
Alexander Brown, P. Christian Schneider, Kevin France +8
The high energy X-ray and ultraviolet (UV) radiation fields of exoplanet host stars play a crucial role in controlling the atmospheric conditions and the potential habitability of…
FUMES III: Ultraviolet and Optical Variability of M Dwarf Chromospheres
Girish M. Duvvuri, J. Sebastian Pineda, Zachory K. Berta-Thompson +2
We obtained ultraviolet and optical spectra for 9 M~dwarfs across a range of rotation periods to determine whether they showed stochastic intrinsic variability distinguishable from…
A Pilot Survey of an M Dwarf Flare Star with Swift's UV Grism
Shashank Chavali, Allison Youngblood, Rishi R. Paudel +5
The near-ultraviolet (NUV) spectral region is a useful diagnostic for stellar flare physics and assessing the energy environment of young exoplanets, especially as relates to prebi…
Intrinsic Lyman alpha Profiles of High-Velocity G, K, and M Dwarfs
Allison Youngblood, J. Sebastian Pineda, Thomas Ayres +5
Observations of H I Lyman alpha, the brightest UV emission line of late-type stars, are critical for understanding stellar chromospheres and transition regions, modeling photochemi…
Giant white-light flares on fully convective stars occur at high latitudes
Ekaterina Ilin, Katja Poppenhaeger, Sarah J. Schmidt +7
White-light flares are magnetically driven localized brightenings on the surfaces of stars. Their temporal, spectral, and statistical properties present a treasury of physical info…
The M-dwarf Ultraviolet Spectroscopic Sample I. Determining Stellar Parameters for Field Stars
J. Sebastian Pineda, Allison Youngblood, Kevin France
Accurate stellar properties are essential for precise stellar astrophysics and exoplanetary science. In the M-dwarf regime, much effort has gone into defining empirical relations t…
FUMES. II. Ly Reconstructions of Young, Active M Dwarfs
Allison Youngblood, J. Sebastian Pineda, Kevin France
The HI Ly (1215.67 $\unicode{xC5}$) emission line dominates the far-UV spectra of M dwarf stars, but strong absorption from neutral hydrogen in the interstellar medium makes obs…
The Far Ultraviolet M-dwarf Evolution Survey. I. The Rotational Evolution of High-Energy Emissions
J. Sebastian Pineda, Allison Youngblood, Kevin France
M-dwarf stars are prime targets for exoplanet searches because of their close proximity and favorable properties for both planet detection and characterization. However, the potent…
The Mega-MUSCLES Spectral Energy Distribution Of TRAPPIST-1
David J. Wilson, Cynthia S. Froning, Girish M. Duvvuri +19
We present a 5A-100um Spectral Energy Distribution (SED) of the ultracool dwarf star TRAPPIST-1, obtained as part of the Mega-MUSCLES Treasury Survey. The SED combines ultraviolet…
Estimating the Ultraviolet Emission of M dwarfs with Exoplanets from Ca II and H
Katherine Melbourne, Allison Youngblood, Kevin France +29
M dwarf stars are excellent candidates around which to search for exoplanets, including temperate, Earth-sized planets. To evaluate the photochemistry of the planetary atmosphere,…
Solar Analogs as a Tool to Understand the Sun
Allison Youngblood, Steve Cranmer, Sam Van Kooten +6
Solar analogs, broadly defined as stars similar to the Sun in mass or spectral type, provide a useful laboratory for exploring the range of Sun-like behaviors and exploring the phy…
On the Correlation between L Dwarf Optical and Infrared Variability and Radio Aurorae
Tyler Richey-Yowell, Melodie M. Kao, J. Sebastian Pineda +2
Photometric variability attributed to cloud phenomena is common in L/T transition brown dwarfs. Recent studies show that such variability may also trace aurorae, suggesting that lo…
Deconfusing the Confusogram: Getting New Insights from Zeeman Doppler Imaging
J. Sebastian Pineda, James R. A. Davenport
Zeeman Doppler Imaging is a powerful tool for characterizing the strength and topology of stellar magnetic fields. In this research note, we present a new way to visualize the typi…
3.8um Imaging of 400-600K Brown Dwarfs and Orbital Constraints for WISEP J045853.90+643452.6AB
S. K. Leggett, Trent J. Dupuy, Caroline V. Morley +10
Half of the energy emitted by late-T- and Y-type brown dwarfs emerges at 3.5 < lambda um < 5.5. We present new L' (3.43 < lambda um < 4.11) photometry obtained at the Gemini North…
Magnetism in the Brown Dwarf Regime
Melodie M. Kao, J. Sebastian Pineda, Peter Williams +8
A suite of discoveries in the last two decades demonstrate that we are now at a point where incorporating magnetic behavior is key for advancing our ability to characterize substel…
A Hot Ultraviolet Flare on the M Dwarf Star GJ 674
C. S. Froning, A. Kowalski, K. France +10
As part of the Mega MUSCLES Hubble Space Telescope (HST) Treasury program, we obtained time-series ultraviolet spectroscopy of the M2.5V star, GJ~674. During the FUV monitoring obs…