Results 141 to 150 of about 4,318,459 (158)

Coordinated Observations of the Red Dwarf Flare Star EV Lac in 1993

Astrophysics and Space Science, 1997
Results of cooperative observations of the flare star EV Lac in September 1993 are presented. One of the about 30 optical flares detected was powerful enough to permit a quantitative analysis of its intrinsic radiation with the colour-colour technique.
E.P. Abranin, L.L. Bazelyan, I.Yu. Alekseev, R.E. Gershberg, S. Avgoloupis, J.H. Seiradakis, L.N. Mavridis, G.M. Beskin, S.N. Mitronova, I.P. Panferova, M.R. Kidger   +10 more
openaire   +1 more source

Chromospheric Lines in Red Dwarf Flare Stars. II. EV Lacertae, EQ Pegasi a, and V1054 Ophiuchi.

Astrophysical Journal, 1984
On presente des observations de profils de raies avec une resolution spectrale de 0,45 A pour trois etoiles M4e semblables, du voisinage solaire, avec une luminosite de 1/60 du Soleil: EV Lacertae, EQ Pegari A et V 1054 Oph. On donne des resultats pour Hα (λ6563), les raies Na D(λλ5890, 5896), He I (λ5876) et les raies triplet infra-rouge Ca II (λλ8498,
B. R. Pettersen, L. A. Coleman, D. S. Evans   +2 more
exaly   +2 more sources

Emission Lines in the Spectrum of the Red-Dwarf Flare Star EV Lac: Modeling of the Quiescent Chromosphere

Astronomy Reports, 2001
We present spectral observations of the red-dwarf flare star EV Lac made at the Crimean Astrophysical Observatory in 1994 and 1995, and describe a method for semi-empirical modeling of the chromospheres of red dwarfs based on their emission spectra.
R E Gershberg
exaly   +2 more sources

Investigation of flare activity of the red dwarf star EV Lac based on original observations and using the data from ground-based and space surveys

2022
The problem of energetics of flare activity of dwarf stars in the lower main sequence of the Hertzsprung-Russell diagram is relevant in the context of the detection of powerful flares (superflares) and the possibility of assessing such phenomena on the Sun in the past and future. A brief historical review of the EV Lac original researches is presented,
Shlyapnikov, A.A., Gorbachev, M.A.
openaire   +1 more source

Flaring red dwarf stars: news from Crimea

Uspekhi Fizicheskih Nauk, 1998
Important phenomena are briefly described which have recently been discovered in the Crimean studies of flaring red dwarf stars believed to be the most common type of variable stars in the Galaxy. These phenomena include (i) long-lived radiation from a blueshifted component in the ionized-helium λ 4686 A emission line in the active state of one such ...
openaire   +1 more source

Spectral observations of red dwarfs II. New observations of flare stars in the Pleiades cluster region

Astrophysics, 1994
We studied the spectra of 24 flare stars of the Pleiades cluster region obtained on the 2.6m telescope of the Byurakan observatory in the years 1986–1989. From the spectral indices of titanium oxide (TiO) and other chemical elements of the stars investigated we determined their spectral classes and luminosities (absolute visual stellar magnitudes). The
L. V. Mirzoyan, V. V. Ambaryan, A. T. Garibdzhanyan   +2 more
openaire   +1 more source

Coordinated observations of the red dwarf flare star EV Lac in 1998

2019
The results of photometric studies of the flare star EV Lac obtained in the course of cooperative observations in 1998 are presented. No significant brightness variations in IR were found from simultaneous observations of the star in UBVRI and H bands, in coincidence with the observed optical flares.
Alekseev, I.Yu., Antov, A.P., Avgoloupis, S.J., Beskin, G.M., Borisov, N.V., Chalenko, V.E., Contadakis, M.E., Gershberg, R.E., Khalak, V.R., Konstantinova-Antova, R.K., Larionov, V.M., Panferova, I.P., Plokhotnichenko, V.L., Pustil???nik, L.A., Romanyuk, Ya.O., Seiradakis, J.-H., Sergeev, S.G., Svyatogorov, O.A., Verlyuk, I.A., Zhilyaev, B.E.   +19 more
openaire   +1 more source

Spectroscopic observations of red dwarfs I. Flare stars in the Pleiades

Astrophysics, 1991
L. V. Mirzoyan, V. V. Ambaryan, A. T. Garibdzhanyan   +2 more
openaire   +1 more source

Flare stars and the evolution of red dwarf stars

Astrophysics, 1994
openaire   +1 more source

Red Dwarfs/Flare Stars

2004
openaire   +1 more source