Results 21 to 30 of about 215 (165)

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
doaj   +1 more source

High Time Resolution Photometry of Red Dwarf Flare Stars II. The Shortest Flare Rise Time [PDF]

International Astronomical Union Colloquium, 1989
AbstractWe have studied the initial phases of 65 optical flares on UV Cet type stars with a time resolution of 3x10–7 s. Ninety per cent of these flares have rapid brightenings shorter than 10 s and several are shorter than 1 s. We detected on UV Cet the shortest flare observed to date with a total duration of 1.7 s and a rise time of 0.3 s.
G.M. Beskin, V.L. Plakhotnichenko, L.A. Pustil'nik, V.F. Shvartsman, R.E. Gershberg   +4 more
openaire   +1 more source

Time resolved spectroscopic observations of an M-dwarf flare star EV Lac during a flare. [PDF]

, 2016
Flares are explosions on the surface of the Sun and stars. We can find stellar flares frequently on M-dwarf stars. EV Lac, one of the M-dwarf flare stars, is a good target for investigation of stellar flares.
Honda, Satoshi (5266576), Nogami, Daisaku, Honda, Satoshi, Shibata, Kazunari, Maehara, Hiroyuki (5266573), Notsu, Shota (5266570), Notsu, Shota, Notsu, Yuta (5266585), Notsu, Yuta, Namekata, Kosuke, Namekata, Kosuke (5301265), Maehara, Hiroyuki, Shibata, Kazunari (5266579), Nogami, Daisaku (5266582)   +13 more
core   +1 more source

High Time Resolution Photometry of Red Dwarf Flare Stars I. A Search For Fine Structures on the Optical Light Curves of Flares [PDF]

International Astronomical Union Colloquium, 1989
AbstractA detailed analysis of 73 flares on UV Cet type stars observed at the 6 m telescope of the Special Astrophysical Observatory with 3x10–7 s time resolution shows no fine structures on flare light curves with time scales from 10–6 to 10–1 s.
G.M. Beskin, S.N. Mitronova, S.I. Neizvestnyj, V.L. Plakhotnichenko, L.A. Pustil'nik, V.F. Shvartsman, R.E. Gershberg   +6 more
openaire   +1 more source

Variability of the He I line at 10 830 Å [PDF]

, 2020
The He  I infrared (IR) triplet at 10 830 Å is known as an activity indicator in solar-type stars and has become a primary diagnostic in exoplanetary transmission spectroscopy.
Schmitt, J. H. M. M., Hintz, D., Nagel, E., Caballero, J. A., Czesla, S., Fuhrmeister, B., Hildebrandt, L., Johnson, E. N., Jeffers, S. V., Schöfer, P., Montes, D.   +10 more
core   +4 more sources

Multi-wavelength Characterization of Stellar Flares on Low-mass Stars Using SDSS and 2 MASS Time-domain Surveys [PDF]

, 2012
We present the first rates of flares from M dwarf stars in both red optical and near-infrared (NIR) filters. We have studied ~50,000 M dwarfs from the Sloan Digital Sky Survey (SDSS) Stripe 82 area and 1321 M dwarfs from the Two Micron All Sky Survey ...
Kowalski, Adam F., Hawley, Suzanne L., Davenport, James R. A., Schmidt, Sarah J., Becker, Andrew C., Hilton, Eric J., Sesar, Branimir, Cutri, Roc   +7 more
core   +1 more source

High Time Resolution Photometry of Red Dwarf Flare Stars III. The Most Rapid and Faintest Observed Stellar Flares; their Physics and Statistics [PDF]

International Astronomical Union Colloquium, 1989
AbstractHigh time resolution monitoring of the UV Cet type flare stars has enabled as to detect flares with total duration of a few seconds and with energy output comparable to solar subflares. We find that the time scales of decay for such flares correspond to recombination times of optically thin gas or to cooling times of optically thick gas heated ...
G.M. Beskin, S.I. Neizvestnyj, V.L. Plakhotnichenko, L.A. Pustil'nik, V.F. Shvartsman, R.E. Gershberg   +5 more
openaire   +1 more source

The high-energy radiation environment around a 10 Gyr M dwarf: habitable at last? [PDF]

, 2020
Recent work has demonstrated that high levels of X-ray and UV activity on young M dwarfs may drive rapid atmospheric escape on temperate, terrestrial planets orbiting within the habitable zone.
Duvvuri, Girish, Vieytes, M., Mauas, Pablo Jacobo David, Berta Thompson, Zachory K., Vieytes, Mariela, Vieytes, Mariela Cristina, Alvarado-Gomez, Julian, Schneider, P. Christian, Mauas, Pablo JD, Loyd, R. O. Parke, Alvarado-Gómez, J.D., France, K., Duvvuri, G., Pineda, J Sebastian, Koskinen, Tommi, Froning, Cynthia S, Berta-Thompson, Z.K., Froning, C.S., France, Kevin, Parke Loyd, R.O., Garraffo, Cecilia, Wilson, David J., Pineda, J. Sebastian, Koskinen, T., Pineda, J.S., Alvarado-Gómez, Julián D., Tian, Feng, Egan, H., Drake, Jeremy, Youngblood, Allison, Schneider, P Christian, Berta-Thompson, Zachory K., Garraffo, C., Kaltenegger, Lisa, Brown, Alexander, Drake, J.J., Mauas, Pablo J. D., Linsky, J.L., Linsky, Jeffrey L., Kaltenegger, L., Miguel, Yamila, Kowalski, Adam F., Rugheimer, Sarah, Kowalski, Adam F, Linsky, Jeffry L, Kowalski, A.F., Miguel, Y., Drake, Jeremy J., Brown, A., Parke Loyd, R. O., Tian, F., Wilson, David J, Mauas, P.J.D., Youngblood, A., Egan, Hilary, Schneider, P.C., Loyd, ROP, Drake, Jeremy J, Berta-Thompson, Zachory K, Froning, Cynthia S., Wilson, D.J., Rugheimer, S., Alvarado Gómez, Julián D.   +62 more
core   +2 more sources

Spectropolarimetric observations of active stars [PDF]

, 1997
This paper reports the results of five years (five runs, 23 nights of spectropolarimetric observations of active stars with the UCL Echelle Spectrograph of the Anglo-Australian Telescope. 225 circularly rand (our linearly) polarized spectra were recorded
Donati, J-F, Carter, BD, Cameron, Andrew Collier, Donati, J. -F., Rees, D. E., Cameron, A. C., Semel, M., Rees, DE, Carter, B. D., Semel, M   +9 more
core   +1 more source

Coronal response to magnetically-suppressed CME events in M-dwarf stars [PDF]

, 2019
We report the results of the first state-of-the-art numerical simulations of Coronal Mass Ejections (CMEs) taking place in realistic magnetic field configurations of moderately active M-dwarf stars.
Drake, Jeremy J., Moschou, Sofia P., Fraschetti, Federico, Yadav, Rakesh K., Garraffo, Cecilia, Alvarado-Gómez, Julián D., Cohen, Ofer   +6 more
core   +1 more source