Microstructure of Jovian decametric S bursts

Carr, T. D.; Reyes, F.

doi:10.1029/1999ja900342

Cited by 34 publications

(55 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These S-bursts (i.e., not demonstrating quasilinear negatively drifting patterns over the time-frequency plane) can be described by the theory of narrow-band random processes as well. Of course, since the instantaneous bandwidth of complex S-bursts is wider, the typical duration of subpulses becomes shorter (as also noticed by Carr and Reyes [1999]). Since time-frequency patterns in a typical S-burst storm demonstrate high variability in shape, the effective bandwidth of the amplifier responsible for generation of S-bursts should be strongly variable.…”

Section: Conclusion and Discussionmentioning

confidence: 72%

“…Such an approach implicitly assumes a harmonic oscillation as an adequate mathematical model that has to be fitted to the measured time series. Carr and Reyes [1999] proposed a short segment of harmonic signal…”

Section: Signal Preprocessing and Hilbert Transformmentioning

confidence: 99%

“…Using a baseband receiver with a half-voltage bandwidth of the order of 280 kHz combined with a tape recorder and data rate slow down technique, Carr and Reyes [1999] achieved a sampling rate equivalent to about 0.3 ms. The most important findings from earlier works can be roughly summarized as follows [Carr and Reyes, 1999;Carr, 2001;Litvinenko et al, 2004].…”

Section: Introductionmentioning

confidence: 99%

“…Contrary to the ideas reported by Carr and Reyes [1999], who focused on modeling subpulses as segments of sinusoidal functions (e.g., generated by coherent bunches of electrons moving along Jovian magnetic field lines), we consider the basic model of Gaussian noise enhanced by a narrow-band resonance amplifier (maser).…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Jupiter S‐bursts: Narrow‐band origin of microsecond subpulses

Ryabov

Vavriv

et al. 2007

J. Geophys. Res.

View full text Add to dashboard Cite

[1] We analyze the records of Jupiter's decameter radio emissions obtained during an Io-A S-burst storm on 15 March 2005. The observations were performed at the world's largest decameter array, UTR-2, which is equipped with a digital receiver capable of catching waveforms of duration $3 s with temporal resolution defined by the sampling rate of $66 MHz. A Hilbert transform based algorithm has been applied to study narrowband spectral patterns demonstrating quasi-linear drift over time-frequency plane. The instantaneous amplitude and phase information has been extracted from the recorded waveforms with the purpose of analyzing microsecond-scale coherent events in the S-burst emission. A statistical model of narrow band random process is proposed for describing such features in the observed waveforms as coherent segments, phase jumps, nonlinear frequency drift, etc. It is shown that the study of coherence properties in terms of instantaneous phase is equivalent to Fourier analysis of a narrowband signal. This implies that no particular mechanism (such as superimposed modulation or oscillation) is required for generating the observed coherent phase structures of S-burst emission: those, as well as the pulse-like envelope structures, emerge naturally at the output of a narrow band filter applied to a random noise. It is further suggested that probability distribution function of instantaneous amplitude gives an important insight into the underlying physical mechanism of S-burst generation. In particular, it is demonstrated that models based on the concept of ''generator,'' i.e., a nonlinear system with feedback, are less suitable for reproducing the observational characteristics of S-bursts at microsecond time scale resolution. On the other hand, the concept of ''amplifier,'' i.e., a linear system (without feedback) that enhances the fluctuations within a narrow band, fits the observational data well. This conclusion is consistent with S-burst generation mechanism via cyclotron-maser instability, which is indeed a resonant wave amplification process.Citation: Ryabov, V. B., B. P. Ryabov, D. M. Vavriv, P. Zarka, R. Kozhin, V. V. Vinogradov, and V. A. Shevchenko (2007), Jupiter S-bursts: Narrow-band origin of microsecond subpulses,

show abstract

Section: Conclusion and Discussionmentioning

confidence: 72%

Section: Signal Preprocessing and Hilbert Transformmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Jupiter S‐bursts: Narrow‐band origin of microsecond subpulses

Ryabov

Vavriv

et al. 2007

J. Geophys. Res.

View full text Add to dashboard Cite

show abstract

“…The negative frequency drift, which is approximately proportional to the radiation frequency, df /dt ∝ f , and a small frequency interval f occupied by the burst, Δf/f ∼ 10 −2 − 10 −1 , are characteristic features of the S emission considered in our work. The pulses of such S emission often form quasiperiodic trains with one or several repetition frequencies in a range of about 2 to 400 kHz in the dynamic spectrum (see, for example, Flagg et al [1976]; Krausche et al [1976]; Riihimaa [1977], and also Carr and Reyes [1999] and references therein). An example of the dynamic spectrum with a train of S-bursts observed in July 6, 1999 (Kharkov, Ukraine) using radio telescopes UTR-2 (Ukrainian T-shape Radio telescope) is shown in Figure 1 [Litvinenko et al 2004].…”

Section: Introductionmentioning

confidence: 99%

Consideration of the Jovian S-bursts and NB-emission Based on the Parametric Model

Шапошников¹,

Костров²,

Rücker³

et al. 2011

Planetary Radio Emissions Vii

View full text Add to dashboard Cite

The new mechanism for the formation of a fine structure in the dynamic spectra of the Jovian decametric radio emission is proposed. The main attention is paid to the formation of narrow-band (NB) emission and quasiperiodic trains of S-bursts. Our model is based on the effects of occurrence of the amplitude-frequency modulation and extension of the frequency spectrum of a signal during propagation of the radiation in a medium with time-varied parameters. It is shown that non-stationary disturbances of the planetary magnetic field and strong frequency dispersion of the plasma at frequencies close to the cutoff frequency of the extraordinary wave in the Jovian ionosphere can play a crucial role in the formation of NB emission and quasiperiodic trains of S-bursts. As a result of the numerical experiments, it was concluded that the amplitude-frequency characteristics of an initially continuous signal can drastically vary as functions of the form of the magnetic-field disturbance in the Jovian ionosphere. Structures similar to those observed in the real experiments, ranging from NB emission and quasiperiodic trains of S-bursts to more complex structures, arise in the dynamic spectrum.

show abstract

Probing Jovian decametric emission with the long wavelength array station 1

et al. 2014

Self Cite

View full text Add to dashboard Cite

New observations of Jupiter's decametric radio emissions have been made with the Long Wavelength Array Station 1 (LWA1), which is capable of making high-quality observations as low as 11 MHz. Full Stokes parameters were determined for bandwidths of 16 MHz. Here we present the first LWA1 results for the study of six Io-related events at temporal resolutions as fine as 0.25 ms. LWA1 data show excellent spectral detail in Jovian DAM such as simultaneous left-hand circular (LHC) and right-hand circular (RHC) polarized Io-related arcs and source envelopes, modulation lane features, S-burst structures, narrow band N events, and interactions between S bursts and N events. The sensitivity of the LWA1 combined with the low-radio-frequency interference environment allow us to trace the start of the LHC Io-C source region to much earlier CML III than typically found in the literature. We find that the Io-C starts as early as CML III = 230• at frequencies near 11 MHz. This early start of the Io-C emission may be valuable for refining models of the emission mechanism. We also detect modulation lane structures that appear continuous across LHC and RHC emissions, suggesting that both polarizations may originate from the same hemisphere of Jupiter. We present a study of rare S bursts detected during an Io-D event and show that drift rates are consistent with those from other Io-related sources. Finally, S-N burst events are seen in high spectral and temporal resolution and our data strongly support the cospatial origins of these events.

show abstract

Microstructure of Jovian decametric S bursts

Cited by 34 publications

References 38 publications

Jupiter S‐bursts: Narrow‐band origin of microsecond subpulses

Jupiter S‐bursts: Narrow‐band origin of microsecond subpulses

Consideration of the Jovian S-bursts and NB-emission Based on the Parametric Model

Probing Jovian decametric emission with the long wavelength array station 1

Contact Info

Product

Resources

About