184 citations · 1.8k across the 52 of their papers we have counts for
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A magnetic field study of two fast-rotating, radio bright M dwarfs. StKM 1-1262 and V374 Peg
S. Bellotti, P. I. Cristofari, J. R. Callingham +8
Radio observations at low frequencies are sensitive to the magnetic activity of stars and the plasma environment surrounding them. The accurate interpretation of the processes unde…
Constraining the Mass Loss and the Kinetic Energy of Solar Coronal Mass Ejections with Far-Ultraviolet Flares
Nuri Park, Evgenya L. Shkolnik, Joe Llama
Stellar eruptive events, such as flares and coronal mass ejections (CMEs), can affect planetary habitability by disturbing the stability of their atmospheres. For instance, strong…
A Dragon's Flame of Many Colours: Multi-wavelength Observations of Flares from the Active M Binary CR Draconis
James A. G. Jackman, Evgenya L. Shkolnik, R. O. Parke Loyd +9
We present the results of a multi-wavelength Pro-Am campaign to study the behaviour of flares from the active M1.5V star binary CR Draconis. CR Dra was observed with TESS 20-s phot…
Refining the Stellar Parameters of Ceti: a Pole-on Solar Analog
Maria Korolik, Rachael M. Roettenbacher, Debra A. Fischer +16
To accurately characterize the planets a star may be hosting, stellar parameters must first be well-determined. Ceti is a nearby solar analog and often a target for exoplanet s…
Flares, Rotation, Activity Cycles and a Magnetic Star-Planet Interaction Hypothesis for the Far Ultraviolet Emission of GJ 436
R. O. Parke Loyd, P. C. Schneider, James A. G. Jackman +6
Variability in the far ultraviolet (FUV) emission produced by stellar activity affects photochemistry and heating in orbiting planetary atmospheres. We present a comprehensive anal…
The IGRINS YSO Survey III: Stellar parameters of pre-main sequence stars in Ophiuchus and Upper Scorpius
Ricardo López-Valdivia, Gregory N. Mace, Eunkyu Han +9
We used the Immersion GRating Infrared Spectrometer (IGRINS) to determine fundamental parameters for 61 K- and M-type young stellar objects (YSOs) located in the Ophiuchus and Uppe…
Constraining the Physical Properties of Stellar Coronal Mass Ejections with Coronal Dimming: Application to Far Ultraviolet Data of Eridani
R. O. Parke Loyd, James Mason, Meng Jin +9
Coronal mass ejections (CMEs) are a prominent contributor to solar system space weather and might have impacted the Sun's early angular momentum evolution. A signal diagnostic of C…
MOVES V. Modelling star-planet magnetic interactions of HD 189733
A. Strugarek, R. Fares, V. Bourrier +10
Magnetic interactions between stars and close-in planets may lead to a detectable signal on the stellar disk. HD 189733 is one of the key exosystems thought to harbor magnetic inte…
The IGRINS YSO Survey I. Stellar parameters of pre-main sequence stars in Taurus-Auriga
Ricardo López-Valdivia, Kimberly R. Sokal, Gregory N. Mace +19
We present fundamental parameters for 110 canonical K- & M-type (1.30.13) Taurus-Auriga young stellar objects (YSOs). The analysis produces a simultaneous determination…
Recovery of TESS Stellar Rotation Periods Using Deep Learning
Zachary R. Claytor, Jennifer L. van Saders, Joe Llama +3
We used a convolutional neural network to infer stellar rotation periods from a set of synthetic light curves simulated with realistic spot evolution patterns. We convolved these s…
Projected Rotational Velocities and Fundamental Properties of Low-Mass Pre-Main Sequence Stars in the Taurus-Auriga Star Forming Region
Larissa A. Nofi, Christopher M. Johns-Krull, Ricardo López-Valdivia +11
The projected stellar rotational velocity () is critical for our understanding of processes related to the evolution of angular momentum in pre-main sequence stars. We pr…
Amplitude Modulation of Short-Timescale Hot Spot Variability
Lauren I. Biddle, Joe Llama, Andrew Collier Cameron +3
Variability of Classical T Tauri Systems (CTTS) occurs over a vast range of timescales. CTTS in particular are subject to variability caused by accretion shocks which can occur sto…
Constraining Stellar Photospheres as an Essential Step for Transmission Spectroscopy of Small Exoplanets
Benjamin V. Rackham, Arazi Pinhas, Dániel Apai +29
Transmission spectra probe the atmospheres of transiting exoplanets, but these observations are also subject to signals introduced by magnetic active regions on host stars. Here we…
MOVES II. Tuning in to the radio environment of HD189733b
R. D. Kavanagh, A. A. Vidotto, D. Ó Fionnagáin +7
We present stellar wind modelling of the hot Jupiter host HD189733, and predict radio emission from the stellar wind and the planet, the latter arising from the interaction of the…
Discovery of a magnetic white dwarf with unusual short-period variability
Aleks Scholz, Joe Llama, Koraljka Muzic +3
We report the discovery of a magnetic white dwarf which shows periodic variability with P=110 min, color-dependent amplitudes and a transient phase shift in the blue compared to th…
Simulating radio emission from Low Mass Stars
Joe Llama, Moira M. Jardine, Kenneth Wood +2
Understanding the origins of stellar radio emission can provide invaluable insight into the strength and geometry of stellar magnetic fields and the resultant space weather environ…
Signatures of Star-planet Interactions
Evgenya L. Shkolnik, Joe Llama
Planets interact with their host stars through gravity, radiation and magnetic fields, and for those giant planets that orbit their stars within ~10 stellar radii (~0.1 AU for a su…
MOVES I. The evolving magnetic field of the planet-hosting star HD189733
R. Fares, V. Bourrier, A. A. Vidotto +9
HD189733 is an active K dwarf that is, with its transiting hot Jupiter, among the most studied exoplanetary systems. In this first paper of the Multiwavelength Observations of an e…
Searching for spectroscopic binaries within transition disk objects
Saul A. Kohn, Evgenya L. Shkolnik, Alycia J. Weinberger +2
Transition disks (TDs) are intermediate stage circumstellar disks characterized by an inner gap within the disk structure. To test whether these gaps may have been formed by closel…
Testing the recovery of stellar rotation signals from Kepler light curves using a blind hare-and-hounds exercise
S. Aigrain, J. Llama, T. Ceillier +10
We present the results of a blind exercise to test the recoverability of stellar rotation and differential rotation in Kepler light curves. The simulated light curves lasted 1000 d…
Mechanical Equilibrium of Hot, Large-Scale Magnetic Loops on T Tauri Stars
Alicia Aarnio, Joe Llama, Moira Jardine +1
The most extended, closed magnetic loops inferred on T Tauri stars confine hot, X-ray emitting plasma at distances from the stellar surface beyond the the X-ray bright corona and c…
Shock formation around planets orbiting M-dwarf stars
A. A. Vidotto, J. Llama, M. Jardine +2
Bow shocks can be formed around planets due to their interaction with the coronal medium of the host stars. The net velocity of the particles impacting on the planet determines the…