Broadband Observations of Radio Emission of Flare Stars

Radio Observations of Flare Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100032814 ◽

1971 ◽

Vol 15 ◽

pp. 114-115

Author(s):

A. J. Wilson

Keyword(s):

Radio Emission ◽

Solar Neighbourhood ◽

Early Type ◽

Radio Observations ◽

Flare Stars

Observations of the radio emission from the red dwarf flare stars in the solar neighbourhood have been made at Jodrell Bank since 1958. In Australia, observations have been made both of these flare stars and of the early type flare stars in stellar aggregates. Observations in both Britain and Australia have been hampered by the difficulties involved in obtaining radio and optical coverage at the same time.In the initial Jodrell Bank programme, at a frequency of 240 mhz, between 1958 and 1960, 474 hours of observations were obtained, mostly on UV Ceti, and 13 events compatible with bursts of radio emission from the star were seen, but due to poor seeing conditions at the Cambridge Observatories the correlation between radio and optical flares could not be established, although the rate of occurence of radio events was similar to the reported rate for optical events of a few magnitudes.

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A search for radio emission from flare stars in the Pleiades

The Astronomical Journal ◽

10.1086/114678 ◽

1988 ◽

Vol 95 ◽

pp. 794 ◽

Cited By ~ 10

Author(s):

T. S. Bastian ◽

G. A. Dulk ◽

O. B. Slee

Keyword(s):

Radio Emission ◽

Flare Stars

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Quiescent And Flaring Radio Emission From dMe Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100096202 ◽

1983 ◽

Vol 71 ◽

pp. 273-286 ◽

Cited By ~ 1

Author(s):

D. M. Gibson

Keyword(s):

Radio Emission ◽

Solar Flares ◽

Expected Value ◽

Detection Thresholds ◽

Significant Interest ◽

Radio Studies ◽

Flare Stars ◽

Ev Lac ◽

M Dwarf

In reviewing radio studies of M-dwarf flare stars one is struck by the curious way in which the field developed. Indeed, that is twenty years old may be the greatest surprise, for if one imagines the largest solar flares occurring at distances comparable to the nearest stars the expected flux densities would be < 10 mJy. Yet, despite the fact that detection thresholds in 1963 were about two orders of magnitude higher than the expected value, Lovell et al. (1963) made extensive observations and reported the. detection of UV Ceti. This remarkable discovery was followed immediately by detections of V371 Ori (Slee et al., 1963) and EV Lac (Lovell et al., 1964). One might have thought that these unexpected discoveries would have spurred significant interest in this new field but they did not.

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Radio Emission from Flare Stars

Flare Stars ◽

10.1016/b978-0-08-023035-1.50020-x ◽

1980 ◽

pp. 264-280

Keyword(s):

Radio Emission ◽

Flare Stars

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Radio emission from flare stars

Solar Physics ◽

10.1007/bf00156794 ◽

1990 ◽

Vol 130 (1-2) ◽

pp. 265-294 ◽

Cited By ~ 41

Author(s):

T. S. Bastian

Keyword(s):

Radio Emission ◽

Flare Stars

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A Search for 843 MHz Radio Emission from Active Stars

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000026953 ◽

1986 ◽

Vol 6 (3) ◽

pp. 319-322

Author(s):

A. E. Vaughan ◽

M. I. Large

Keyword(s):

Radio Emission ◽

Time Scale ◽

Low Frequency ◽

Active Stars ◽

Flare Stars

AbstractKnown Southern flare stars and RSCVn-like variables are being observed with the Molonglo Observatory Synthesis Telescope in an attempt to detect quiescent (non-flaring) emission. Two flare stars out of 7 and one RSCVn out of 8 have been detected. Quiescent emission has not been observed previously from these sources at such a low frequency. All sources so far detected have mean flux densities below 10 mJy and in at least two of them the emission varies with a time scale of about one day.

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Two Alternative Mechanisms for Very Bright Radio Emission from Flare Stars

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000025790 ◽

1993 ◽

Vol 10 (3) ◽

pp. 254-257 ◽

Cited By ~ 2

Author(s):

D.B. Melrose

Keyword(s):

Radio Emission ◽

Brightness Temperature ◽

Second Harmonic ◽

Temporal Variations ◽

Plasma Emission ◽

High Brightness ◽

Circular Polarisation ◽

Cyclotron Maser ◽

Flare Stars ◽

High Degree

AbstractThe bright radio emission from flare stars has three characteristic properties: high brightness temperature, high degree of circular polarisation and rapid temporal variations. Two proposed emission mechanisms, electron cyclotron maser emission (ECME) and plasma emission, are compared and contrasted. It is argued that although the important features of the emission can be explained in terms of either ECME or plasma emission, all three favor ECME. However, the escapes of the radiation through the second harmonic absorption layer remains inadequately understood, and as a consequence doubts about the ECME interpretation remain.

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Non-thermal electrons and stellar radio emission

International Astronomical Union Colloquium ◽

10.1017/s0252921100153758 ◽

1989 ◽

Vol 104 (2) ◽

pp. 37-40

Author(s):

S. M. White ◽

M. R. Kundu

Keyword(s):

Radio Emission ◽

Brightness Temperature ◽

Solar Radio ◽

Thermal Emission ◽

The Sun ◽

Apparent Brightness ◽

Flare Stars ◽

Apparent Brightness Temperature

AbstractRadio emission from dMe flare stars has both a flaring and a quiescent component. When we compare stellar radio emission with the Sun, however, we find that the apparent brightness temperature of the quiescent component often exceeds the temperature of non-thermal solar radio flares, and so it is likely that stellar quiescent emission also comes from non-thermal electrons. The duration of stellar quiescent emission is much longer than solar non-thermal emission. Obvious questions to ask are, what is the source of the non-thermal electrons, where do they reside, and how can non-thermal emission last so long? Here we briefly review the observations of quiescent emission, argue that the emitting regions are small, show that such small regions can still account for the observed fluxes, and discuss the source of electrons.

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