scholarly journals Turbulent Sound Generation in Red Dwarf Stars

1983 ◽  
Vol 71 ◽  
pp. 605-608
Author(s):  
H.U. Bonn
Keyword(s):  
Current Model ◽  
Solar Chromosphere ◽  
Sound Generation ◽  
Dwarf Star ◽  
Dwarf Stars ◽  
Model Calculations ◽  
Red Dwarf Stars

Since the acoustic heating theory (c.f. Ulmschneider 1979) has been proven successful for the solar chromosphere, it was common practice to extend this concept to other stars. However, as it appeares from observed chromospheric and coronal emissions, the usual theoretical acoustic fluxes for red dwarf star, particularly, are too small to account for the heating of chromospheres and coronae (e.g. Blanco et al 1974; Vaiana et al, 198l) . It is therefore the intention of this paper to discuss improvements on the current model calculations for turbulent sound generation from outer convection zones.

scholarly journals The Red Dwarf Star Population in the Galaxy

1995 ◽  
Vol 151 ◽  
pp. 55-56 ◽  
Author(s):  
L.V. Mirzoyan
Keyword(s):  
Star Clusters ◽  
Space Distribution ◽  
Dwarf Star ◽  
Star Clusters And Associations ◽  
Dwarf Stars ◽  
The Galaxy ◽  
Flare Stars ◽  
Red Dwarf Stars ◽  
T Tau ◽  
Stellar Associations

Red dwarf stars in the Galaxy occur in three forms: as flare stars, T Tau stars and red dwarf stars of constant brightness. Haro (1957) suggested that all these stars present regular evolutionary stages of red dwarf stars.The space distribution of UV Cet flare stars in the solar vicinity indicates that these low luminosity stars belong to the disk population of the Galaxy. Therefore one can suppose that all red dwarf stars have a space distribution which is similar to that of the flare stars (Mirzoyan et al. 1988a). Only a small part of them is found in star clusters and associations. The T Tau stars are an exception: because of their very short lifetime, all of them are found in stellar associations.The space distribution of red dwarf stars is determined by the fact that all of them are formed in star clusters and associations and are finally lost from their stellar systems and merge into the general galactic field (Mirzoyan 1995).

Flaring red dwarf stars: news from Crimea

1998 ◽  
Vol 168 (8) ◽  
pp. 891 ◽  
Author(s):  
Roald E. Gershberg
Keyword(s):  
Dwarf Stars ◽  
Red Dwarf Stars

scholarly journals Double-Peaked Flare Events on red Dwarf Stars and Solar ‘Sympathetic’ Flares

1976 ◽  
Vol 71 ◽  
pp. 475-475
Author(s):  
M. Rodonò
Keyword(s):  
Proximity Effect ◽  
Binary Systems ◽  
Angular Separation ◽  
Dwarf Stars ◽  
Multiple Systems ◽  
Photometric Observations ◽  
Red Dwarfs ◽  
Flare Stars ◽  
Red Dwarf Stars ◽  
The Individual

About 50% of the flare events observed on red dwarfs are at least double-peaked. As the majority of flare stars are members of double or multiple systems, the possibility that time-overlapping flares originate quasi-simultaneously on the individual components is discussed.Assuming a poissonian occurrence of flares in both components, the expected probability of observing double-peaked flares is lower than 1% for the most active binary systems.However, from photometric observations of the double flare star EQ Peg (BD +19°5116 AB) carried out by the author with an area scanner (the components' angular separation is 3.7″) about 20% of the observed flares have been found to be double-peaked flares resulting from separate flares, one in each component. A direct flare triggering of the following flare by the preceding one can be ruled out since the light travel-time between the two components is 3.5 h, while the observed time delay between the flare peaks is about 10 min. Moreover, the proximity effect does not seem to play an important triggering role.It is concluded that, although the analogy with solar ‘sympathetic’ flares is not always applicable, it is the most promising framework within which the majority of double-peaked flare events on red dwarfs must be interpreted.

scholarly journals Speckle Interferometry of Red Dwarf Stars

2018 ◽  
Vol 155 (5) ◽  
pp. 215 ◽  
Author(s):  
Brian D. Mason ◽  
William I. Hartkopf ◽  
Korie N. Miles ◽  
John P. Subasavage ◽  
Deepak Raghavan ◽  
...  
Keyword(s):  
Speckle Interferometry ◽  
Dwarf Stars ◽  
Red Dwarf Stars

scholarly journals The ITA Survey on Red Dwarf Variable Stars – Final Report

1983 ◽  
Vol 71 ◽  
pp. 175-177
Author(s):  
C.A.O. Torres ◽  
I.C. Busko ◽  
G.R. Quast
Keyword(s):  
Variable Stars ◽  
Final Report ◽  
Dwarf Stars ◽  
Red Dwarf Stars ◽  
Almost All

From 1971 to 1973, an observational survey on red dwarf stars to search for possible periodic photometric variations was carried out at ITA Observatory - Brazil. Two observing runs at Cerro Tololo in 1974 and 1975 were used as an extension of this survey. We observed a total of 90 stars, as shown in Table I, and almost all stars were measured at least five times during the same season.

Properties of Radiative Shock Waves in the Atmospheres of Red Dwarf Stars

Astrophysics ◽  
2019 ◽  
Vol 62 (2) ◽  
pp. 234-250 ◽  
Author(s):  
O. M. Belova ◽  
K. V. Bychkov
Keyword(s):  
Shock Waves ◽  
Dwarf Stars ◽  
Radiative Shock ◽  
Red Dwarf Stars

scholarly journals Flares on Red Dwarf Stars as a Result of the Dynamical Response of the Chromosphere to the Heating

1983 ◽  
Vol 71 ◽  
pp. 617-619
Author(s):  
M.M. Katsova ◽  
M.A. Livshits
Keyword(s):  
Thermal Conductivity ◽  
Solar Flare ◽  
Secondary Process ◽  
Dynamical Response ◽  
Radio Bursts ◽  
Hard Phase ◽  
Dwarf Stars ◽  
X Ray ◽  
Microwave Radio ◽  
Red Dwarf Stars

The impulsive hard X-ray, EUV and microwave radio bursts always start at or after the onset of a soft X-ray increase - the main phase of a solar flare - before the Hα flare maximum. This hard phase of a solar flare lasts ~ 100 s and consists of several elementary bursts of 10 s duration. In this time electrons are accelerated up to energy 20-100 keV, then they are injected vertically downwards into denser chromospheric layers. The electron heating as well as the thermal conductivity heating leads to the appearance of the secondary process, in particular, to gasdynamical motions (Kostyuk and Pikel'ner, 1940.

scholarly journals A Report on Flare Stars on the Sproul Astrometric Program

1971 ◽  
Vol 15 ◽  
pp. 109-109
Author(s):  
Sarah Lee Lippincott
Keyword(s):  
Long Range ◽  
Dwarf Stars ◽  
Nearby Stars ◽  
Flare Stars ◽  
Red Dwarf Stars ◽  
O 10 ◽  
Photographic Records

The long range program of the Sproul Observatory initiated in 1937 by P. VAN DE KAMP has been primarily devoted to a detailed astrometric study of the positions of nearby stars from photographs taken with the 24-inch refractor. By now there are 30 years of observations on most stars with parallaxes greater than + O″10 and brighter than the 12th magnitude which are observable at latitude +40°. It follows therefore that there are long series of photographic records of many red dwarf stars.

Narrow-band radio flares from red dwarf stars

1986 ◽  
Vol 311 ◽  
pp. 814 ◽  
Author(s):  
Stephen M. White ◽  
Mukul R. Kundu ◽  
Peter D. Jackson
Keyword(s):  
Narrow Band ◽  
Dwarf Stars ◽  
Red Dwarf Stars
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