246 citations · 1.4k across the 52 of their papers we have counts for
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Understanding the Duration of Solar and Stellar Flares at Various Wavelengths
Jeffrey W. Reep, Vladimir S. Airapetian
Recent irradiance measurements from numerous heliophysics and astrophysics missions including SDO, GOES, Kepler, TESS, Chandra, XMM-Newton, and NICER have provided critical input i…
Non-thermal motions and atmospheric heating of cool stars
S. Boro Saikia, T. Lueftinger, V. S. Airapetian +6
The magnetic processes associated with the non-thermal broadening of optically thin emission lines appear to carry enough energy to heat the corona and accelerate the solar wind. W…
Reconstructing the XUV Spectra of Active Sun-like Stars Using Solar Scaling Relations with Magnetic Flux
Kosuke Namekata, Shin Toriumi, Vladimir S. Airapetian +3
Kepler Space Telescope and Transiting Exoplanet Survey Satellite unveiled that Sun-like stars frequently host exoplanets. These exoplanets are subject to fluxes of ionizing radiati…
Universal Scaling Laws for Solar and Stellar Atmospheric Heating: Catalog of Power-law Index between Solar Activity Proxies and Various Spectral Irradiances
Shin Toriumi, Vladimir S. Airapetian, Kosuke Namekata +1
The formation of extremely hot outer atmospheres is one of the most prominent manifestations of magnetic activity common to the late-type dwarf stars, including the Sun. It is wide…
Universal Scaling Laws for Solar and Stellar Atmospheric Heating
Shin Toriumi, Vladimir S. Airapetian
The Sun and sun-like stars commonly host the multi-million-Kelvin coronae and the 10,000-Kelvin chromospheres. These extremely hot gases generate X-ray and Extreme Ultraviolet emis…
Evolution of X-ray Activity in <25 Myr Old Pre-Main Sequence Stars
Konstantin V. Getman, Eric D. Feigelson, Gordon P. Garmire +4
Measuring the evolution of X-ray emission from pre-main sequence (PMS) stars gives insight into two issues: the response of magnetic dynamo processes to changes in interior structu…
One Year in the Life of Young Suns: Data Constrained Corona-Wind Model of kappa1 Ceti
Vladimir S. Airapetian, Meng Jin, Theresa Lueftinger +5
The young magnetically active solar-like stars are efficient generators of ionizing radiation in the form of X-ray and Extreme UV (EUV) flux, stellar wind and eruptive events. Thes…
From Starspots to Stellar Coronal Mass Ejections -- Revisiting Empirical Stellar Relations
Konstantin Herbst, Athanasios Papaioannou, Vladimir S. Airapetian +1
Upcoming missions, including the James Webb Space Telescope, will soon characterize the atmospheres of terrestrial-type exoplanets in habitable zones around cool K- and M-type star…
Sun-as-a-star Spectral Irradiance Observations of Transiting Active Regions
Shin Toriumi, Vladimir S. Airapetian, Hugh S. Hudson +3
Major solar flares are prone to occur in active region atmospheres associated with large, complex, dynamically-evolving sunspots. This points to the importance of monitoring the ev…
The solar wind from a stellar perspective: how do low-resolution data impact the determination of wind properties?
S. Boro Saikia, M. Jin, C. P. Johnstone +5
Alfvén-wave-driven 3D magnetohydrodynamic (MHD) models, which are increasingly used to predict stellar wind properties, contain unconstrained parameters and rely on low-resolution…
Frequency of Coronal Mass Ejection Impacts with Early Terrestrial Planets and Exoplanets Around Active Solar-like Stars
Christina Kay, Vladimir S. Airapetian, Theresa Lüftinger +1
Energetic flares and associated coronal mass ejections (CMEs) from young magnetically active solar-like stars can play a critical role in setting conditions for atmospheric escape…
Constraining stellar parameters and atmospheric dynamics of the carbon AGB star V Oph
Gioia Rau, Keiichi Ohnaka, Markus Wittkowski +2
Molecules and dust produced by the atmospheres of cool evolved stars contribute to a significant amount of the total material found in the interstellar medium. To understand the me…
Impact of Stellar Superflares on Planetary Habitability
Yosuke A. Yamashiki, Hiroyuki Maehara, Vladimir Airapetian +15
High-energy radiation caused by exoplanetary space weather events from planet-hosting stars can play a crucial role in conditions promoting or destroying habitability in addition t…
Effect of Star Rotation Rates on the Characteristics of Energetic Particle Events
Shuai Fu, Yong Jiang, Vladimir Airapetian +3
Recent detection of superflares on solar-type stars by Kepler mission raised a possibility that they can be associated with energetic coronal mass ejections (CMEs) and energetic pa…
Cool, evolved stars: results, challenges, and promises for the next decade
Gioia Rau, Rodolfo Montez, Kenneth G. Carpenter +27
Cool, evolved stars are the main source of chemical enrichment of the interstellar medium (ISM), and understanding their mass loss and structure offers a unique opportunity to stud…
GHRS Observations of Cool, Low-Gravity Stars. VI Mass-Loss Rates and Wind Parameters for M Giants
Gioia Rau, Krister E. Nielsen, Kenneth G. Carpenter +1
The photon-scattering winds of M-giants absorb parts of the chromospheric emission lines and produce self-reversed spectral features in high resolution {\it HST}/GHRS spectra. Thes…
3D Global Coronal Density Structure and Associated Magnetic Field near Solar Maximum
Maxim Kramar, Vladimir Airapetian, Haosheng Lin
Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal dynamic phenomena at all scales. We employ STEREO/COR1 data obtained…
Reconstructing the Solar Wind From Its Early History To Current Epoch
Vladimir S. Airapetian, Arcadi V. Usmanov
Stellar winds from active solar type stars can play a crucial role in removal of stellar angular momentum and erosion of planetary atmospheres. However, major wind properties excep…
Magnetic Interaction of a Super-CME with the Earth's Magnetosphere: Scenario for Young Earth
Vladimir S. Airapetian, Alex Glocer, William Danchi
Solar eruptions, known as Coronal Mass Ejections (CMEs), are frequently observed on our Sun. Recent Kepler observations of superflares on G-type stars have implied that so called s…
Atmospheric Heating and Wind Acceleration: Results for Cool Evolved Stars based on Proposed Processes
Vladimir S. Airapetian, Manfred Cuntz
A chromosphere is a universal attribute of stars of spectral type later than ~F5. Evolved (K and M) giants and supergiants (including the zeta Aurigae binaries) show extended and h…
Stellar Wind Erosion of Protoplanetary Discs
Neesha R. Schnepf, Richard V. E. Lovelace, Marina Romanova +1
An analytic model is developed for the erosion of protoplanetary gas discs by high velocity magnetized stellar winds. The winds are centrifugally driven from the surface of rapidly…
Stellar Imager (SI): developing and testing a predictive dynamo model for the Sun by imaging other stars
Kenneth G. Carpenter, Carolus J. Schrijver, Margarita Karovska +39
The Stellar Imager mission concept is a space-based UV/Optical interferometer designed to resolve surface magnetic activity and subsurface structure and flows of a population of Su…
Winds from Luminous Late-Type Stars: II. Broadband Frequency Distribution of Alfvén Waves
Vladimir Airapetian, Kenneth G. Carpenter, Leon Ofman
We present the numerical simulations of winds from evolved giant stars using a fully non-linear, time dependent 2.5-dimensional magnetohydrodynamic (MHD) code. This study extends o…