406 citations · 1.4k across the 23 of their papers we have counts for
23 papers
Chromospheric sensitivity of stellar spectral lines: an unsupervised machine learning classification
Juan I. Peralta, Mariela C. Vieytes
Stellar magnetic activity alters thousands of spectral lines, limiting high-precision radial-velocity measurements, abundance analyses, and planetary characterization. We present a…
HWO Target Stars and Systems: Activity and Rotation Catalog (ARC) of Potential Target Stars for the Habitable Worlds Observatory
Tara Fetherolf, Arvind F. Gupta, Elisabeth R. Newton +7
A major goal of the Habitable Worlds Observatory (HWO) is to precisely characterize exoplanets and their atmospheres. However, magnetic activity from an exoplanet's host star can c…
The influence of chromospheric activity on line formation
Mariela C. Vieytes, Lily L. Zhao, Megan Bedell
One of the primary sources of stellar spectral variability is magnetic activity. While our current understanding of chromospheric activity is largely derived from specific lines se…
The Mega-MUSCLES Treasury Survey: X-ray to infrared Spectral Energy Distributions of a representative sample of M dwarfs
David J. Wilson, Cynthia S. Froning, Girish M. Duvvuri +15
We present 5-1x10^7 Angstrom spectral energy distributions (SEDs) for twelve M dwarf stars covering spectral types M0-M8. Our SEDs are provided for community use as a sequel to the…
The Fe i lines and the chromospheric activity
M. C. Vieytes
Neutral Fe lines are the most abundant in the spectrum of late stars. They are used to obtain different basic stellar parameters such as relative abundances, surface gravity, and e…
Modeling the Mg I from the NUV to MIR. II. Testing stellar models
J. I. Peralta, M. C. Vieytes, A. M. P. Mendez +1
Aims. We tested the new atomic model using atmospheric models of stars of different spectral types: the Sun (dG2), HD22049 (dK2, Epsilon Eridani), GJ 832 (dM2), and GJ 581 (dM3). M…
Modeling the MgI from the NUV to MIR: I. The Solar Case
J. I. Peralta, M. C. Vieytes, A. M. P. Mendez +1
Semi-empirical models of the solar atmosphere are used to study the radiative environment of any planet in our solar system. There is a need for reliable atomic data for neutral at…
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…
Reconstructing the Extreme Ultraviolet Emission of Cool Dwarfs Using Differential Emission Measure Polynomials
Girish M. Duvvuri, J. Sebastian Pineda, Zachory K. Berta-Thompson +16
Characterizing the atmospheres of planets orbiting M dwarfs requires understanding the spectral energy distributions of M dwarfs over planetary lifetimes. Surveys like MUSCLES, HAZ…
Semi-Empirical Modeling of the Atmospheres of the M Dwarf Exoplanet Hosts GJ 832 and GJ 581
Dennis Tilipman, Mariela Vieytes, Jeffrey L. Linsky +2
Stellar ultraviolet (UV) radiation drives photochemistry, and extreme-ultraviolet (EUV) radiation drives mass loss in exoplanet atmospheres. However, the UV flux is partly unobserv…
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,…
The relative emission from chromospheres and coronae: dependence on spectral type and age
Jeffrey L. Linsky, Brian E. Wood, Allison Youngblood +12
Extreme-ultraviolet and X-ray emissions from stellar coronae drive mass loss from exoplanet atmospheres, and ultraviolet emission from stellar chromospheres drives photo-chemistry…
The High-Energy Radiation Environment Around a 10 Gyr M Dwarf: Habitable at Last?
Kevin France, Girish Duvvuri, Hilary Egan +20
High levels of X-ray and UV activity on young M dwarfs may drive rapid atmospheric escape on temperate, terrestrial planets orbiting within the liquid water habitable zone. However…
The MUSCLES Treasury Survey IV: Scaling Relations for Ultraviolet, Ca II K, and Energetic Particle Fluxes from M Dwarfs
Allison Youngblood, Kevin France, R. O. Parke Loyd +18
Characterizing the UV spectral energy distribution (SED) of an exoplanet host star is critically important for assessing its planet's potential habitability, particularly for M dwa…
The MUSCLES Treasury Survey I: Motivation and Overview
Kevin France, R. O. Parke Loyd, Allison Youngblood +18
Ground- and space-based planet searches employing radial velocity techniques and transit photometry have detected thousands of planet-hosting stars in the Milky Way. The chemistry…
Characterizing the Habitable Zones of Exoplanetary Systems with a Large Ultraviolet/Visible/Near-IR Space Observatory
Kevin France, Evgenya Shkolnik, Jeffrey Linsky +32
Understanding the surface and atmospheric conditions of Earth-size, rocky planets in the habitable zones (HZs) of low-mass stars is currently one of the greatest astronomical endea…
High Stellar FUV/NUV Ratio and Oxygen Contents in the Atmospheres of Potentially Habitable Planets
Feng Tian, Kevin France, Jeffrey L. Linsky +2
Recent observations of several planet-hosting M dwarfs show that most have FUV/NUV flux ratios 1000 times greater than that of the Sun. Here we show that the atmospheric oxygen con…
Improving the Ni I atomic model for solar and stellar atmospheric models
Mariela C. Vieytes, Juan M. Fontenla
Neutral nickel (Ni I) is abundant in the solar atmosphere and is one of the important elements that contribute to the emission and absorption of radiation in the spectral range bet…
The Ultraviolet Radiation Environment Around M dwarf Exoplanet Host Stars
Kevin France, Cynthia S. Froning, Jeffrey L. Linsky +8
The spectral and temporal behavior of exoplanet host stars is a critical input to models of the chemistry and evolution of planetary atmospheres. At present, little observational o…
12 Years of Stellar Activity Observations in Argentina
Pablo J. D. Mauas, A. Buccino, R. Diaz +6
We present an observational program we started in 1999, to systematically obtain mid-resolution spectra of late-type stars, to study in particular chromospheric activity. In partic…
Modelling chromospheric line profiles as diagnostics of velocity fields in ω Centauri red giant stars
M. Vieytes, P. Mauas, C. Cacciari +2
Context. Mass loss of ~0.1-0.3 M from Population II red giant stars (RGB) is a requirement of stellar evolution theory in order to account for several observational evide…
Chromospheric changes in K stars with activity
Mariela Vieytes, Pablo Mauas, Rodrigo Diaz
We study the differences in chromospheric structure induced in K stars by stellar activity, to expand our previous work for G stars, including the Sun as a star. We selected six st…
Pulsar wind nebulae around the southern pulsars PSR B1643-43 and PSR B1706-44
E. Giacani, D. A. Frail, W. M. Goss +1
We present high resolution VLA images taken at the wavelengths of lambda 20 cm, lambda 6 cm, and lambda 3.6 cm in the vicinity of the pulsars PSR B1706-44 (PSR J1709-4428) and PSR…