Solar Drift Pair Bursts in the Decameter Range

Melnik, V. N.; Konovalenko, A. A.; Dorovskyy, V. V.; Rücker, H. O.; Abranin, E. P.; Lisachenko, V. N.; Lecacheux, A.

doi:10.1007/s11207-005-8272-4

Cited by 23 publications

(38 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Besides, the drift rate of a single Sburst depends on the frequency, whereas the drift rates of DP elements do not. Also the functional dependences of the drift rates on frequency differ considerably for the DP and S-bursts: it is steeper for both forward and reverse DPs (Melnik et al, 2005).…”

Section: Discussionmentioning

confidence: 96%

“…Other bursts (type III bursts, type IIIb bursts, type III-like bursts, drift pairs, spikes, striae, type II and IV bursts) have durations from 1 s up to 1 hour and even more (Melnik et al, 2005(Melnik et al, , 2008a(Melnik et al, , 2008b. The profile of S-bursts is symmetrical ( Figure 5).…”

Section: Duration Of S-burstsmentioning

confidence: 95%

“…Unlike type III bursts, which have a continuous track in the whole frequency range from 10 to 30 MHz, the frequency band over which a single S-burst may extend varies from 1 -2 MHz to 10 -12 MHz. For comparison: the corresponding value for the drift pairs is only 2 -3 MHz (Melnik et al, 2005).…”

Section: S-burst Events During 27 -30 July 2002mentioning

confidence: 99%

See 2 more Smart Citations

Solar S-bursts at Frequencies of 10 – 30 MHz

Melnik¹,

Konovalenko²,

Rücker³

et al. 2010

Sol Phys

Self Cite

View full text Add to dashboard Cite

Solar S-bursts observed by the radio telescope UTR-2 in the period 2001 -2002 are studied. The bursts chosen for a detailed analysis occurred in the periods 23 -26 May 2001, 13 -16 and 27 -39 July 2002 during three solar radio storms. More than 800 S-bursts were registered in these days. Properties of S-bursts are studied in the frequency band 10 -30 MHz. All bursts were always observed against a background of other solar radio activity such as type III and IIIb bursts, type III-like bursts, drift pairs and spikes. Moreover, Sbursts were observed during days when the active region was situated near the central meridian. Characteristic durations of S-bursts were about 0.35 and 0.4 -0.6 s for the May and July storms, respectively. For the first time, we found that the instantaneous frequency width of S-bursts increased with frequency linearly. The dependence of drift rates on frequency followed the McConnell dependence derived for higher frequencies. We propose a model of S-bursts based on the assumption that these bursts are generated due to the confluence of Langmuir waves with fast magnetosonic waves, whose phase and group velocities are equal.

show abstract

Section: Discussionmentioning

confidence: 96%

Section: Duration Of S-burstsmentioning

confidence: 95%

See 1 more Smart Citation

Solar S-bursts at Frequencies of 10 – 30 MHz

Melnik¹,

Konovalenko²,

Rücker³

et al. 2010

Sol Phys

Self Cite

View full text Add to dashboard Cite

show abstract

“…Chains of stria of type III like bursts, named type IIIb (Ellis & McCulloch 1967;de La Noe & Boischot 1972) are frequently observed and appear to be precursors of type III emission. Emissions of short duration and limited frequency extent are also detected as isolated drift pairs (Roberts 1958;Warwick & Dulk 1969;de La Noe & Moller Pedersen 1971;Melnik et al 2005), consisting of fundamental and harmonic radio emission, usually related to the presence of type III bursts.…”

Section: Introductionmentioning

confidence: 99%

Faint solar radio structures from decametric observations

Briand¹,

Zaslavsky

Maksimović³

et al. 2008

A&A

Self Cite

View full text Add to dashboard Cite

Aims. Decameter radio observations of the solar corona reveal the presence of numerous faint frequency drifting emissions, similar to "solar S bursts" which are reported in the literature. We present a statistical analysis of the characteristics of these emissions and propose a mechanism to excite the Langmuir waves thought to be at the origin of these emissions. Methods. The observations were performed between 1998 and 2002 with the Digital Spectro Polarimeter (DSP) receivers operated at the UTR-2 and Nançay decameter radio telescopes in the frequency range 15-30 MHz. Our theoretical explanation is based on Vlasov-Ampère simulations.Results. Based on the frequency drift rate, three populations of structures can be identified. The largest population presents an average negative frequency drift of −0.9 MHz s −1 and a lifetime up to 11 s (median value of 2.72 s). A second population shows a very small frequency drift of −0.1 MHz s −1 and a short lifetime of about 1 s. The third population presents an average positive frequency drift of +0.95 MHz s −1 and a lifetime of up to 3 s. Also, the frequency drift as a function of frequency is consistent with the former results, which present results in higher frequency range. No specific relationship was found between the occurrence of these emissions and the solar cycle or presence of flares. Assuming that these emissions are produced by "electron clouds" propagating the solar corona, we deduce electron velocities of about 3-5 times the electron thermal velocity. As previously shown, a localized, time-dependent modulation of the electron distribution function (heating) leads to low velocity electron clouds (consistent with observations), which, in turn, can generate Langmuir waves and electromagnetic signals by nonlinear processes.

show abstract

“…The frequency separation between some fibers slightly increases with time (see Figure 6 of Chernov et al, 2007b). WIND/WAVES) also detected the presence of fine structure in type II bursts at decametric and longer wavelengths (Bougeret et al, 1995;Melnik et al, 2005).…”

Section: Introductionmentioning

confidence: 93%

An Investigation of the Role of Propagation Effects in the Formation of Drifting Narrowband Type II Fiber Bursts on the Dynamic Spectrum

Afanasiev

2010

Sol Phys

View full text Add to dashboard Cite

This paper investigates one of the kinds of fine structure of solar decametric type II radio bursts in the form of drifting narrowband fibers. The appearance of such a structure is customarily explained by the features of the radio emission mechanism in the source, which is formed when the shock wave catches up the previously-generated coronal mass ejection. On the other hand, the characteristics of radio emission in the process of its propagation from the source to the observation point are affected by inhomogeneities in the corona. Hence it is of considerable interest to estimate the role of the propagation effects on the formation of fiber structures in radio bursts. Our calculations show that strong refraction effects (caustics) can give rise to narrowband structures in the dynamic spectrum, resembling in their characteristics the fibers observed.

show abstract

Solar Drift Pair Bursts in the Decameter Range

Cited by 23 publications

References 9 publications

Solar S-bursts at Frequencies of 10 – 30 MHz

Solar S-bursts at Frequencies of 10 – 30 MHz

Faint solar radio structures from decametric observations

An Investigation of the Role of Propagation Effects in the Formation of Drifting Narrowband Type II Fiber Bursts on the Dynamic Spectrum

Contact Info

Product

Resources

About