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View article: Constraining the Mass Loss and the Kinetic Energy of Solar Coronal Mass Ejections with Far-Ultraviolet Flares
Constraining the Mass Loss and the Kinetic Energy of Solar Coronal Mass Ejections with Far-Ultraviolet Flares Open
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 stellar flares and CMEs can trigger atmospheric escape and,…
View article: Granulation on a quiet K dwarf: HD 166620 I. Spectral signatures as a function of line-formation temperature
Granulation on a quiet K dwarf: HD 166620 I. Spectral signatures as a function of line-formation temperature Open
As radial velocity (RV) spectrographs reach unprecedented precision and stability below 1 m s$^{-1}$, the challenge of granulation in the context of exoplanet detection has intensified. Despite promising advancements in post-processing too…
View article: Stringent Limits on H$_3^+$ Emission from the Hot Jupiters WASP-80b and WASP-69b
Stringent Limits on H$_3^+$ Emission from the Hot Jupiters WASP-80b and WASP-69b Open
Observations of auroras on exoplanets would provide numerous insights into planet-star systems, including potential detections of the planetary magnetic fields, constraints on host-star wind properties, and information on the thermal struc…
View article: Seasonal Changes in the Atmosphere of HD 80606b Observed with JWST's NIRSpec/G395H
Seasonal Changes in the Atmosphere of HD 80606b Observed with JWST's NIRSpec/G395H Open
High-eccentricity gas giant planets serve as unique laboratories for studying the thermal and chemical properties of H/He-dominated atmospheres. One of the most extreme cases is HD 80606b -- a hot Jupiter orbiting a sun-like star with an e…
View article: The Lowell Observatory Solar Telescope: A fiber feed into the EXtreme PREcision Spectrometer
The Lowell Observatory Solar Telescope: A fiber feed into the EXtreme PREcision Spectrometer Open
The signal induced by a temperate, terrestrial planet orbiting a Sun-like star is an order of magnitude smaller than the host stars' intrinsic variability. Understanding stellar activity is, therefore, a fundamental obstacle in confirming …
View article: The Lowell Observatory Solar Telescope: a fiber feed into the Extreme Precision Spectrometer
The Lowell Observatory Solar Telescope: a fiber feed into the Extreme Precision Spectrometer Open
The signal induced by a temperate, terrestrial planet orbiting a Sun-like\nstar is an order of magnitude smaller than the host stars' intrinsic\nvariability. Understanding stellar activity is, therefore, a fundamental\nobstacle in confirmi…
View article: Planet Hunters TESS. V. A Planetary System Around a Binary Star, Including a Mini-Neptune in the Habitable Zone
Planet Hunters TESS. V. A Planetary System Around a Binary Star, Including a Mini-Neptune in the Habitable Zone Open
We report on the discovery and validation of a transiting long-period mini-Neptune orbiting a bright ( V = 9.0 mag) G dwarf (TOI 4633; R = 1.05 R ⊙ , M = 1.10 M ⊙ ). The planet was identified in data from the Transiting Exoplanet Survey Sa…
View article: The POKEMON Speckle Survey of Nearby M Dwarfs. III. The Stellar Multiplicity Rate of M Dwarfs within 15 pc
The POKEMON Speckle Survey of Nearby M Dwarfs. III. The Stellar Multiplicity Rate of M Dwarfs within 15 pc Open
M dwarfs are ubiquitous in our Galaxy, and the rate at which they host stellar companions, and the properties of these companions, provide a window into the formation and evolution of the star(s), and of any planets that they may host. The…
View article: A dragon’s flame of many colours: multiwavelength observations of flares from the active M binary CR Draconis
A dragon’s flame of many colours: multiwavelength observations of flares from the active M binary CR Draconis Open
We present the results of a multiwavelength Professional–Amateur campaign to study the behaviour of flares from the active M1.5V star binary CR Draconis. CR Dra was observed with Transiting Exoplanet Survey Satellite (TESS) 20-s photometry…
View article: A Dragon's Flame of Many Colours: Multi-wavelength Observations of Flares from the Active M Binary CR Draconis
A Dragon's Flame of Many Colours: Multi-wavelength Observations of Flares from the Active M Binary CR Draconis Open
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 photometry, Swift near-UV (NUV) grism spectroscopy and with gro…
View article: The POKEMON Speckle Survey of Nearby M Dwarfs. III. The Stellar Multiplicity Rate of M Dwarfs within 15 pc
The POKEMON Speckle Survey of Nearby M Dwarfs. III. The Stellar Multiplicity Rate of M Dwarfs within 15 pc Open
M dwarfs are ubiquitous in our galaxy, and the rate at which they host stellar companions, and the properties of these companions, provides a window into the formation and evolution of the star(s), and of any planets that they may host. Th…
View article: The POKEMON Speckle Survey of Nearby M Dwarfs. II. Observations of 1125 Targets
The POKEMON Speckle Survey of Nearby M Dwarfs. II. Observations of 1125 Targets Open
Stellar multiplicity is correlated with many stellar properties, yet multiplicity measurements have proven difficult for the M dwarfs—the most common type of star in our galaxy—due to their faintness and the fact that a reasonably complete…
View article: Precise Radial Velocities Using Line Bisectors
Precise Radial Velocities Using Line Bisectors Open
We study the properties of line bisectors in the spectrum of the Sun-as-a-star, as observed using the Integrated Sunlight Spectrometer (ISS) of the SOLIS project. Our motivation is to determine whether changes in line shape due to magnetic…
View article: Precise Radial Velocities Using Line Bisectors
Precise Radial Velocities Using Line Bisectors Open
We study the properties of line bisectors in the spectrum of the Sun-as-a-star, as observed using the Integrated Sunlight Spectrometer (ISS) of the SOLIS project. Our motivation is to determine whether changes in line shape, due to magneti…
View article: The POKEMON Speckle Survey of Nearby M Dwarfs. II. Observations of 1125 Targets
The POKEMON Speckle Survey of Nearby M Dwarfs. II. Observations of 1125 Targets Open
Stellar multiplicity is correlated with many stellar properties, yet multiplicity measurements have proven difficult for the M dwarfs -- the most common type of star in our galaxy -- due to their faintness and the fact that a reasonably-co…
View article: The Extreme Stellar-signals Project. III. Combining Solar Data from HARPS, HARPS-N, EXPRES, and NEID
The Extreme Stellar-signals Project. III. Combining Solar Data from HARPS, HARPS-N, EXPRES, and NEID Open
We present an analysis of Sun-as-a-star observations from four different high-resolution, stabilized spectrographs -- HARPS, HARPS-N, EXPRES, and NEID. With simultaneous observations of the Sun from four different instruments, we are able …
View article: The Extreme Stellar-signals Project. III. Combining Solar Data from HARPS, HARPS-N, EXPRES, and NEID
The Extreme Stellar-signals Project. III. Combining Solar Data from HARPS, HARPS-N, EXPRES, and NEID Open
We present an analysis of Sun-as-a-star observations from four different high-resolution, stabilized spectrographs—HARPS, HARPS-N, EXPRES, and NEID. With simultaneous observations of the Sun from four different instruments, we are able to …
View article: An Untargeted Survey of the Rotational Properties of Main-belt Asteroids using the Transiting Exoplanet Survey Satellite (TESS)
An Untargeted Survey of the Rotational Properties of Main-belt Asteroids using the Transiting Exoplanet Survey Satellite (TESS) Open
We present photometric data for minor planets observed by the Transiting Exoplanet Survey Satellite during its Cycle 1 operations. In total, we extracted usable detections for 37,965 objects. We present an examination of the reliability of…
View article: Refining the Stellar Parameters of τ Ceti: a Pole-on Solar Analog
Refining the Stellar Parameters of τ Ceti: a Pole-on Solar Analog Open
To accurately characterize the planets a star may be hosting, stellar parameters must first be well determined. τ Ceti is a nearby solar analog and often a target for exoplanet searches. Uncertainties in the observed rotational velocities …
View article: The igrins yso survey. i. stellar parameters of pre-main-sequence stars in taurus- auriga
The igrins yso survey. i. stellar parameters of pre-main-sequence stars in taurus- auriga Open
We present fundamental parameters for 110 canonical K- and M-type (1.3-0.13Me) Taurus-Auriga young stellar objects (YSOs). The analysis produces a simultaneous determination of effective temperature (Teff), surface gravity (log g), magneti…
View article: Refining the Stellar Parameters of $τ$ Ceti: a Pole-on Solar Analog
Refining the Stellar Parameters of $τ$ Ceti: a Pole-on Solar Analog Open
To accurately characterize the planets a star may be hosting, stellar parameters must first be well-determined. $τ$ Ceti is a nearby solar analog and often a target for exoplanet searches. Uncertainties in the observed rotational velocitie…
View article: EXPRES. IV. Two Additional Planets Orbiting ρ Coronae Borealis Reveal Uncommon System Architecture
EXPRES. IV. Two Additional Planets Orbiting ρ Coronae Borealis Reveal Uncommon System Architecture Open
Thousands of exoplanet detections have been made over the last 25 years using Doppler observations, transit photometry, direct imaging, and astrometry. Each of these methods is sensitive to different ranges of orbital separations and plane…
View article: EXPRES IV: Two Additional Planets Orbiting $ρ$ Coronae Borealis Reveal Uncommon System Architecture
EXPRES IV: Two Additional Planets Orbiting $ρ$ Coronae Borealis Reveal Uncommon System Architecture Open
Thousands of exoplanet detections have been made over the last twenty-five years using Doppler observations, transit photometry, direct imaging, and astrometry. Each of these methods is sensitive to different ranges of orbital separations …
View article: A Radiative-convective Model for Terrestrial Planets with Self-consistent Patchy Clouds
A Radiative-convective Model for Terrestrial Planets with Self-consistent Patchy Clouds Open
Clouds are ubiquitous: they arise for every solar system planet that possesses an atmosphere and have also been suggested as a leading mechanism for obscuring spectral features in exoplanet observations. As exoplanet observations continue …
View article: Flares, Rotation, Activity Cycles, and a Magnetic Star–Planet Interaction Hypothesis for the Far-ultraviolet Emission of GJ 436
Flares, Rotation, Activity Cycles, and a Magnetic Star–Planet Interaction Hypothesis for the Far-ultraviolet Emission of GJ 436 Open
Variability in the far-ultraviolet (FUV) emission produced by stellar activity affects photochemistry and heating in orbiting planetary atmospheres. We present a comprehensive analysis of the FUV variability of GJ 436, a field-age M2.5V st…
View article: Flares, Rotation, Activity Cycles and a Magnetic Star-Planet Interaction Hypothesis for the Far Ultraviolet Emission of GJ 436
Flares, Rotation, Activity Cycles and a Magnetic Star-Planet Interaction Hypothesis for the Far Ultraviolet Emission of GJ 436 Open
Variability in the far ultraviolet (FUV) emission produced by stellar activity affects photochemistry and heating in orbiting planetary atmospheres. We present a comprehensive analysis of the FUV variability of GJ 436, a field-age, M2.5V s…
View article: The IGRINS YSO Survey. III. Stellar Parameters of Pre-main-sequence Stars in Ophiuchus and Upper Scorpius
The IGRINS YSO Survey. III. Stellar Parameters of Pre-main-sequence Stars in Ophiuchus and Upper Scorpius Open
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 Upper Scorpius star-forming regions. We employed synthetic spec…
View article: The IGRINS YSO Survey III: Stellar parameters of pre-main sequence stars in Ophiuchus and Upper Scorpius
The IGRINS YSO Survey III: Stellar parameters of pre-main sequence stars in Ophiuchus and Upper Scorpius Open
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 Upper Scorpius star-forming regions. We employed synthetic spec…