Multiple-Frequency Measurements of a Flare Continuum Event

1982 ◽  
Vol 4 (4) ◽  
pp. 389-392 ◽  
Author(s):  
R.D. Robinson
Keyword(s):  
Solar Flares ◽  
Electromagnetic Waves ◽  
Plasma Frequency ◽  
Close Association ◽  
Type Ii ◽  
Multiple Frequency ◽  
Langmuir Waves ◽  
Long Duration ◽  
Type Ii Radio Bursts ◽  
The Continuum

A type of metre-wavelength continuum is observed in close association with solar flares and Type II radio bursts. This continuum is stationary in position, often intense, of a long duration (occasionally lasting well over an hour) and highly polarized (Robinson and Smerd 1975; Robinson 1978). It is thought to be produced by the conversion of Langmuir waves to electromagnetic waves near the local plasma frequency. Because of its close association with Type II bursts, the class has been designated as Type II related flare continuum, or FCII. In this paper I examine a particularly clear example of such an event, with emphasis on the relation between the Type II and the start of the continuum.

scholarly journals Investigation of Drift Rate of Solar Radio Burst Type II due to Coronal Mass Ejections Phenomenon

2015 ◽  
Vol 48 ◽  
pp. 146-154 ◽  
Author(s):  
N.H. Zainol ◽  
Zety Sharizat Hamidi ◽  
N.N.M. Shariff ◽  
S. Arifin ◽  
C. Monstein
Keyword(s):  
Radio Burst ◽  
Coronal Mass Ejections ◽  
Solar Radio ◽  
Drift Rate ◽  
Plasma Frequency ◽  
Low Cost ◽  
Solar Radio Burst ◽  
Type Ii ◽  
Langmuir Waves ◽  
Low Drift

The formation of detected solar radio burst type II occurred was captured using Compound Astronomical Low Cost Frequency Spectrometer Transportable Observatory (CALLISTO) system which gives a better resolution of a wonderful image than other countries. The phenomenon was found on 2nd November 2014 at 09:39 [UT] in Switzerland. CALLISTO spectrometer device detects and traces a Coronal Mass Ejections (CMEs) phenomenon that causes the occurrence of the solar burst type II. As it happened, the drift rate of the solar radio burst Type II is calculated and discussed in details. Plasma frequency (fp), Langmuir waves and type II radiation relates each other in the establishment of this phenomenon. This paper presents a study of drift rate selected event of solar radio burst type II based on CMEs. The drift rate at this moment was about 3.2 MHz/s which has low drift rate thus the velocity OF THE CMEs was just about 695 km/s shown from NOAA.

scholarly journals Solar Radio Emission of Spectral Type IV and its Association with Geomagnetic Storms

1959 ◽  
Vol 12 (4) ◽  
pp. 404 ◽  
Author(s):  
DJ McLean
Keyword(s):  
Solar Flares ◽  
Solar Radio ◽  
Geomagnetic Storms ◽  
Close Association ◽  
Solar Radio Emission ◽  
Type I ◽  
Type Ii ◽  
Type Iv ◽  
New Type ◽  
Radio Event

A new type of solar radio event, the type IV storm, first described by Boischot, has been identified on Dapto radio.spectrographic records. It has been shown to be distinguishable from type I storms by (i) its smooth spectrum, (ii) its close association with type II bursts, and (iii) its remarkably close association with geomagnetic storms. In common with some type I storms, all type IV storms are found to be associated with very large solar flares.

Solar flares associated coronal mass ejections in case of type II radio bursts

2016 ◽  
Vol 361 (8) ◽  
Author(s):  
Beena Bhatt ◽  
Lalan Prasad ◽  
Harish Chandra ◽  
Suman Garia
Keyword(s):  
Coronal Mass Ejections ◽  
Solar Flares ◽  
Radio Bursts ◽  
Type Ii ◽  
Type Ii Radio Bursts

scholarly journals Velocities of Shock Fronts in Solar Corona Generating Type II Radio Bursts at Metre Wavelengths

1962 ◽  
Vol 15 (1) ◽  
pp. 120
Author(s):  
M Krishnamurthi ◽  
G Sivarama Sastry ◽  
T Seshagiri Rao
Keyword(s):  
Shock Front ◽  
Solar Corona ◽  
Solar Flares ◽  
Radio Bursts ◽  
Type Ii ◽  
Plasma Oscillations ◽  
Slow Drift ◽  
Type Ii Radio Bursts ◽  
Shock Fronts ◽  
Comprehensive Study

At the time of intense solar flares, various types of enhanced radio emission from the Sun have been observed. Using such techniques as the swept frequency technique first developed by Wild and his associates, these enhanced emissions have been classified into five types. Of particular interest to radio astronomy at metre wavelengths is the slow drift type II bursts. A comprehensive study of these bursts has been made by Roberts (1959). It is now supposed that at the start of a flare an explosion occurs in the lower regions of the solar atmosphere ejecting a column of gas which travels radially outward from the region of the flare. This column of gas is bounded by a shock front which moves forward relative to this gas. This shock front is assumed to excite plasma oscillations in the solar corona giving rise to type II radiation. Velocities of these shock fronts have been determined by various workers.

scholarly journals Mode Conversion and Reflection of Langmuir Waves in an Inhomogeneous Solar Wind

2001 ◽  
Vol 18 (4) ◽  
pp. 355-360 ◽  
Author(s):  
A. J. Willes ◽  
Iver H. Cairns
Keyword(s):  
Solar Wind ◽  
Electromagnetic Waves ◽  
Plasma Frequency ◽  
Mode Conversion ◽  
Langmuir Wave ◽  
Solar Wind Plasma ◽  
Langmuir Waves ◽  
Transverse Electromagnetic ◽  
Solar Wind Parameters ◽  
Conversion Efficiencies

AbstractBeam-driven Langmuir waves in the solar wind are generated just above the electron plasma frequency, which fluctuates in the inhomogeneous solar wind plasma. Consequently, propagating Langmuir waves encounter regions in which the wave frequency is less than the local plasma frequency, where they can be reflected, mode converted to transverse electromagnetic waves, and trapped in density wells. The aim here is to investigate Langmuir wave reflection and mode conversion at a linear density gradient for typical solar wind parameters. It is shown that higher mode conversion efficiencies are possible than previously calculated, but that mode conversion occurs in a smaller region of parameter space. In addition, the possibility of detecting mode conversion with in situ spacecraft Langmuir wave observations is discussed.

scholarly journals Nonlinear generation of the fundamental radiation in plasmas: the influence of induced ion-acoustic and Langmuir waves

1992 ◽  
Vol 48 (1) ◽  
pp. 71-84 ◽  
Author(s):  
F. B. Rizzato ◽  
A. C.-L. Chian
Keyword(s):  
Electromagnetic Waves ◽  
Plasma Frequency ◽  
Low Frequency ◽  
Emission Mechanism ◽  
Langmuir Waves ◽  
Laboratory Plasmas ◽  
Ion Acoustic ◽  
Present Context ◽  
Fundamental Radiation ◽  
Stream Instability

A nonlinear emission mechanism of electromagnetic waves at the fundamental plasma frequency has been examined by Chian & Alves. This mechanism is based on the electromagnetic oscillating two-stream instability driven by two oppositely propagating Langmuir waves. The excitation of the electromagnetic oscillating two-stream instability is due to nonlinear wave–wave coupling involving Langmuir waves, low-frequency density waves and electromagnetic waves. In this paper the Chian & Alves model is improved using the generalized Zakharov equations. Attention is directed toward the influence of induced low-frequency and Langmuir waves on the properties of the electromagnetic oscillating two-stream instability. Presumably, the properties derived in the present context may be relevant to both space and laboratory plasmas.

Sign in / Sign up

Export Citation Format

Share Document