Results 1 to 10 of about 2,541 (217)

Stellar flares

Living Reviews in Solar Physics
Magnetic storms on stars manifest as remarkable, randomly occurring changes of the luminosity over durations that are tiny in comparison to the normal evolution of stars.
Adam F. Kowalski
doaj   +2 more sources

Constraints on Stellar Flare Energy Ratios in the NUV and Optical from a Multiwavelength Study of GALEX and Kepler Flare Stars

The Astrophysical Journal, 2023
We present a multiwavelength study of stellar flares on primarily G-type stars using overlapping time domain surveys in the near-ultraviolet (NUV) and optical regimes. The NUV (the Galaxy Evolution Explorer; GALEX) and optical (Kepler) wavelength domains
C. E. Brasseur, Rachel A. Osten, Isaiah I. Tristan, Adam F. Kowalski   +3 more
doaj   +1 more source

LOW-POWER SOLAR FLARES OF OPTICAL AND X-RAY WAVELENGTHS FOR SOLAR CYCLES 21–24

Solar-Terrestrial Physics, 2020
Using data obtained in optical and X-ray wavelengths, we have analyzed solar flare activity for cycles 21–24. Over the last three cycles, solar activity is shown to decrease significantly.
A.V. Borovik , A.A. Zhdanov
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Chandra, HST/STIS, NICER, Swift, and TESS Detail the Flare Evolution of the Repeating Nuclear Transient ASASSN -14ko

The Astrophysical Journal, 2023
ASASSN-14ko is a nuclear transient at the center of the AGN ESO 253−G003 that undergoes periodic flares. Optical flares were first observed in 2014 by the All-Sky Automated Survey for Supernovae (ASAS-SN) and their peak times are well-modeled with a ...
Anna V. Payne, Katie Auchettl, Benjamin J. Shappee, Christopher S. Kochanek, Patricia T. Boyd, Thomas W.-S. Holoien, Michael M. Fausnaugh, Chris Ashall, Jason T. Hinkle, Patrick J. Vallely, K. Z. Stanek, Todd A. Thompson   +11 more
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Dynamics of small-scale magnetic fields before small and large solar flares

Solar-Terrestrial Physics, 2023
We have examined the dynamics of the longitudinal magnetic field of active region NOAA 12673, using data from the Solar Dynamics Observatory (SDO). During the passage of the active region (AR) across the solar disk, its spots and background fields showed
Borovik A. V., Zhdanov A. A.
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X-Ray, Near-ultraviolet, and Optical Flares Produced by Colliding Magnetospheres in the Young High-eccentricity Binary DQ Tau

The Astrophysical Journal, 2023
DQ Tau is a unique young high-eccentricity binary system that exhibits regular magnetic reconnection flares and pulsed accretion near periastron. We conducted NuSTAR, Swift, and Chandra observations during the 2022 July 30 periastron to characterize X ...
Konstantin V. Getman, Ágnes Kóspál, Nicole Arulanantham, Dmitry A. Semenov, Grigorii V. Smirnov-Pinchukov, Sierk E. van Terwisga   +5 more
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Statistical studies of low-power solar flares. Distribution of flares by area, brightness, and classes

Solar-Terrestrial Physics, 2017
An electronic database has been created for 123801 solar flares that occurred on the Sun over the period from 1972 to 2010. It is based on catalogs of the Solar Geophysical Data (SGD) and Quarterly Bulletin on Solar Activity.
Borovik A.V., Zhdanov A.A.
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Statistical Signatures of Nanoflare Activity. III. Evidence of Enhanced Nanoflaring Rates in Fully Convective stars as Observed by the NGTS

The Astrophysical Journal, 2023
Previous examinations of fully convective M-dwarf stars have highlighted enhanced rates of nanoflare activity on these distant stellar sources. However, the specific role the convective boundary, which is believed to be present for spectral types earlier
S. D. T. Grant, D. B. Jess, C. J. Dillon, M. Mathioudakis, C. A. Watson, J. A. G. Jackman, D. G. Jackson, P. J. Wheatley, M. R. Goad, S. L. Casewell, D. R. Anderson, M. R. Burleigh, R. G. West, J. I. Vines   +13 more
doaj   +1 more source

A 7 Day Multiwavelength Flare Campaign on AU Mic. I. High-time-resolution Light Curves and the Thermal Empirical Neupert Effect

The Astrophysical Journal, 2023
We present light curves and flares from a 7 day, multiwavelength observational campaign of AU Mic, a young and active dM1e star with exoplanets and a debris disk. We report on 73 unique flares between the X-ray to optical data.
Isaiah I. Tristan, Yuta Notsu, Adam F. Kowalski, Alexander Brown, John P. Wisniewski, Rachel A. Osten, Eliot H. Vrijmoet, Graeme L. White, Brad D. Carter, Carol A. Grady, Todd J. Henry, Rodrigo H. Hinojosa, Jamie R. Lomax, James E. Neff, Leonardo A. Paredes, Jack Soutter   +15 more
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Multiwavelength Observations of 6 BL Lac Objects in 2008-2012

EPJ Web of Conferences, 2013
We present results of 4 years of VLBA monitoring along with γ-ray and optical R-band photometric observations of 6 BL Lac objects (3C 66A, S5 0716+71, PKS 0735+17, S4 0954+68, W Com, and OT 081).
Morozova D.A., Jorstad S.G., Marscher A.P., Larionov V.M., Troitskiy I.S., Blinov D.A., Agudo I., Smith P.S.   +7 more
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