Litvinenko, G. V. (1); Rucker, H. O. (2); Lecacheux, A

Slides:



Advertisements
Similar presentations
References [1] Handy, B.N., et al. Solar Phys., 187, 229, [2] Aschwanden, M.J., & Alexander, D., Solar Phys., 204, 91, [3] Khodachenko, M.L.,
Advertisements

Planets and Solar System Science at Low Frequencies Philippe Zarka LESIA, CNRS-Observatoire de Paris France Towards a European.
M. J. Reiner, 1 st STEREO Workshop, March, 2002, Paris.
Which describes a variation of wave frequency ω(t) in a geometric-optic approximation [4]. Here n(ω) is the refractive index of the medium, is the vector.
SOLAR MICROWAVE DRIFTING SPIKES AND SOLITARY KINETIC ALFVEN WAVES D. J. Wu, J. Huang, J. F. Tang, and Y. H. Yan The Astrophysical Journal, 665: L171–L174,
Solar wind in the outer heliosphere: IPS observations at the decameter wavelengths. N.N. Kalinichenko, I.S. Falkovich, A.A. Konovalenko, M.R. Olyak, I.N.
Solar corona observations at decameter wavelengths Artem Koval Institute of Radio Astronomy Kharkov, Ukraine.
Harbin Institute of Technology (Weihai) 1 Chapter 2 Channel Measurement and simulation  2.1 Introduction  Experimental and simulation techniques  The.
Search for the Gravitational Wave Memory effect with the Parkes Pulsar Timing Array Jingbo Wang 1,2,3, Hobbs George 3, Dick Manchester 3, Na Wang 1,4 1.
Radio Interference Calculations
Workshop on Earthquakes: Ground- based and Space Observations 1 1 Space Research Institute, Austrian Academy of Science, Graz, Austria 2 Institute of Physics,
Lecture 1 Signals in the Time and Frequency Domains
COMMUNICATION THEORY.
ABSTRACT This work concerns with the analysis and modelling of possible magnetohydrodynamic response of plasma of the solar low atmosphere (upper chromosphere,
Chapter 9 Electromagnetic Waves. 9.2 ELECTROMAGNETIC WAVES.
References Cohen, L., Proc. IEEE, 77, 72, 1989; Shkelev, E.I., Kislyakov, A.G., Lupov, S, Yu., Radiophys.& Quant.Electronics, 45, 433, Wigner, E.P.,
200 MG 500 MG TheoryObservation Authors Institutes RE J is a hydrogen rich strongly magnetic white dwarf discovered as an EUV source by the ROSAT.
Random Media in Radio Astronomy Atmospherepath length ~ 6 Km Ionospherepath length ~100 Km Interstellar Plasma path length ~ pc (3 x Km)
Importance Of Very Low Frequency Radio Signal Data Registered By VLF-receiver System A. Nina, V. Čadež and V. Srećković Institute of Physics, Belgrade,
Solar observation modes: Commissioning and operational C. Vocks and G. Mann 1. Spectrometer and imaging modes 2. Commissioning proposals 3. Operational.
Remote Radio Sounding Science For JIMO J. L. Green, B. W. Reinisch, P. Song, S. F. Fung, R. F. Benson, W. W. L. Taylor, J. F. Cooper, L. Garcia, D. Gallagher,
20 September 2005Double Star -Cluster Noordwijk Sept WBD Studies of AKR: Coordinated Observations of Aurora and the SAKR – Ion Hole Connection R.
Results Study of Carrier Dynamics in ZnSe Based Scintillators by Frequency Domain Lifetime Measurements J.Mickevičius, P.Vitta, G.Tamulaitis, A. Žukauskas.
STAMMS Conference Meeting, Orleans, France May 2003 R. L. Mutel, D. A. Gurnett, I. Christopher, M. Schlax University of Iowa Spatial and Temporal Properties.
Simultaneous monitoring observations of solar active regions at millimeter wavelengths at radio telescopes RT-7.5 BMSTU (Russia) and RT-14 Metsahovi radio.
Short Time Fourier Transform-based method for fast transients detection Centre for eResearch, University of Auckland, New Zealand,
(1) Institute of Radio Astronomy, Kharkov, Ukraine (2) Space Research Institute, Graz, Austria Decameter Type IV bursts: Properties of Fiber Bursts V.N.
Single Pulse Investigations at the Decameter Range O.M. Ulyanov 1, V.V. Zakharenko 1, V.S. Nikolaenko 1, A. Deshpande 2, M.V. Popov 3, V.A. Soglasnov 3,
TYPE IV BURSTS AT FREQUENCIES MHz V.N. Melnik (1), H.O. Rucker (2), A.A. Konovalenko (1), E.P. Abranin (1), V.V. Dorovskyy(1), A. A. Stanislavskyy.
The investigations of the solar wind with the large decametric radio telescopes of Ukraine Falkovych I.S. 1, Konovalenko A.A 1, Kalinichenko N.N. 1, Olyak.
TO THE POSSIBILITY OF STUDY OF THE EXTERNAL SOLAR WIND THIN STRUCTURE IN DECAMETER RADIO WAVES Marina Olyak Institute of Radio Astronomy, 4 Chervonopraporna,
Type III radio bursts observed with LOFAR and Nançay radioheliograph Jasmina Magdalenić 1, C. Marqué 1, A. Kerdraon 2, G. Mann 3, F. Breitling 3, C. Vocks.
DYNAMIC OF ELECTROMAGNETIC EMISSION DURING THE PERIOD OF SOLAR EXTREME EVENTS M.S.Durasova, V.M.Fridman, T.S.Podstrigach, O.A.Sheiner, S.D.Snegirev, Yu.V.Tikhomirov.
Intrinsic Short Term Variability in W3-OH and W49N Hydroxyl Masers W.M. Goss National Radio Astronomy Observatory Socorro, New Mexico, USA A.A. Deshpande,
GP 1.30 (0553) NARROW BAND NOISE ATTENUATION FOR FMCW SOUNDING Alexey A. Kolchev, Andrey O. Shiriy Mari State University Lenin sq., 1 Yoshkar-Ola, Mari.
On the Role of Electric Field Changes when Calculating Thunderstorm Currents Yu.V. Shlugaev, V.V. Klimenko, E.A. Mareev Institute of Applied Physics RAS,
SUBDIFFUSION OF BEAMS THROUGH INTERPLANETARY AND INTERSTELLAR MEDIA Aleksander Stanislavsky Institute of Radio Astronomy, 4 Chervonopraporna St., Kharkov.
The spatial and temporal distribution of solar and galactic cosmic rays S. V. Tasenko 1, P. V. Shatov 1, I. A. Skorokhodov 1, I. V. Getselev 1,2, M. Podzolko.
-1- Coronal Faraday Rotation of Occulted Radio Signals M. K. Bird Argelander-Institut für Astronomie, Universität Bonn International Colloquium on Scattering.
Comparison of the electron density profiles measured with the Incoherent Scatter Radar, Digisonde DPS-4 and Chirp-Ionosonde Ratovsky K.G., Shpynev* B.G.,
Coronal scattering under strong regular refraction Alexander Afanasiev Institute of Solar-Terrestrial Physics Irkutsk, Russia.
The Space Weather Week Monique Pick LESIA, Observatoire de Paris November 2006.
A Sample IHY 2007 Instrumentation Proposal J. Kasper, B. Thompson, N. Fox.
Low Frequency Array (LOFAR): The French LOFAR Super Station Helmut O. Rucker Commission for Astronomy Austrian Academy of Sciences ÖAW, Vienna, Dec 14.
Global Structure of the Inner Solar Wind and it's Dynamic in the Solar Activity Cycle from IPS Observations with Multi-Beam Radio Telescope BSA LPI Chashei.
RPWI Team Meeting, Sep. 2010, Roma Magnetic Loop Antenna (MLA) Scientific Objectives A. Marchaudon, V. Krasnoselskikh, T. Dudok de Wit, C. Cavoit,
Inherent Length Scales and Apparent Frequencies of Periodic Solar Wind Number Density Structures Nicholeen Viall 1, Larry Kepko 2 and Harlan Spence 1 1.
Solar observations with single LOFAR stations C. Vocks 1. Introduction: Solar Radio radiation 2. Observations with single LOFAR stations 3. Spectrometer.
Do Luminous Infrared Galaxies -LIRGs- follow Hubble’s Law? Harrison Rivera Colon and Yesenia M. Rivera Lopez; Antonio Lucchetti Voc. H.S., Arecibo, Puerto.
Radio emissions from RHESSI TGFs A. Mezentsev 1, N. Østgaard 1, T. Gjesteland 1, K. Albrechtsen 1, M.Marisaldi 1, 2, D. Smith 3 and S. Cummer 4 (1) Birkeland.
RFI Protection Activities in IAA RAS
Solar and heliosheric WG
Chengming Tan National Astronomical Observatories
Interplanetary scintillation of strong sources during the descending phase near the minimum of 23 solar activity cycle Chashei I1., Glubokova1,2 S., Glyantsev1,2.
G. Mevi1,2, G. Muscari1, P. P. Bertagnolio1, I. Fiorucci1
RFI Protection Activities in IAA RAS
EVOLUTION OF LUMINOSITY-LINEAR SIZE RELATION
SWAVES-like radio instrument?
Characterization of Field Line Topologies Near the Magnetopause Using Electron Pitch Angle Measurements D. S. Payne1, M. Argall1, R. Torbert1, I. Dors1,
WITH LOW FREQUENCY UKRAINIAN RADIO TELESCOPES UTR-2, URAN and GURT
Section 2: Science as a Process
G.V. Litvinenko, A.A. Konovalenko, H.O. Rucker,
Section 1: Tools of Astronomy
Veronika S. Kobets Institute of Solar-Terrestrial Physics
An Arecibo HI 21-cm Absorption Survey of Rich Abell Clusters
Series of high-frequency slowly drifting structure mapping the magnetic field reconnection M. Karlicky, A&A, 2004, 417,325.
Observations of pulsar microstructure with the GMRT
GRB spectral evolution: from complex profile to basic structure
GRB spectral evolution: from complex profile to basic structure
Evidence for magnetic reconnection in the high corona
Presentation transcript:

Modulation features on the dynamic spectra of the Jovian sporadic DAM emission. Litvinenko, G. V. (1); Rucker, H.O. (2); Lecacheux, A. (3); Konovalenko, A. A. (1); Vinogradov V.V. (1); Shaposhnikov V.E. (4); Taubenschuss, U. (2) Institute of Radio Astronomy, Kharkov, Ukraine; (2) Space Research Institute, Graz, Austria; (3) CNRS & Observatoire de Paris, France; (4) Institute of Applied Physics, Nizhny Novgorod, Russia. ABSTRACT: Analysis of the large number of the Jovian sporadic decameter emission dynamic spectra allows confidently concluding that practically all observed radiation is in some way modulated. In each specific case the nature of modulation can be different. A mechanism that generates S-bursts can itself create modulation processes as well as the initial emission characteristics can be changed along the propagation path from the source region to the observer (Jupiter magnetosphere, interplanetary medium, Earth ionosphere). Depending on the time and frequency resolution achieved in the experiment and also on the visualization time scale, different features of the radiation spectra appear on the Jovian dynamic spectra. In spite of an extensive investigation of DAM radiation, detailed description and analysis of the modulation events with the different frequency-time scales are not fully available. In connection to this the following questions are interesting: 1) the statistical set of the modulation events: their dependence or independence on Jupiter – Io – observer position, season time, day-night time, the Solar activity; 2) the strong definition of the observed parameters: sign and value of the frequency drift, lane’s curvature, modulation depth, distances between the nearest lanes and their variety, scale of the modulation; 3) the careful study of the reliability of already proposed mechanisms, i.e. diffraction model of Riihimaa and Imai, Cotton-Muton effect, Faraday rotation of the polarization ellipse, scintillation on the Earth ionosphere disturbance (for instance, on the structure of the Traveling Ionospheric Disturbances) and so on. The major attention in the present work is centered on the different unusual features of the modulation effects observing in the dynamic spectra of the Jovian decameter emission. INTRODUCTION Different modulations effects observed on the Jovian S-emission dynamic spectra were discovered and studied by several authors [Riihimaa, 1979; Genova et al., 1981, Imai et al., 1997]. For the first time Riihimaa described the so called “modulation lanes”, groups of lanes drifting in the time-frequency plane. He founded that on the spectra these lanes can have positive or negative sign of drift, and, in some cases, their superposition. Firstly Riihimaa and then Imai proposed an “interference screen” model for the explanation of modulation lanes origin. Genova et al. depicted a new class of modulations, “high frequency lanes”. Moreover, these authors, based on the analysis of big amount of the experimental data, suggested the selection criteria for the modulation events produced either by the Earth’s ionosphere or by the interplanetary medium oscillations. In the work of Ryabov [2001], the evolution of S-bursts fine structure was studied against a background of the multi-scale spectra of Io-depending radio-burst emission. Ryabov [2001] marked a repetition of the self-similar burst images with the different scale on the frequency-time plane. Carr and Reyes [1999], Litvinenko et al., [2004] using the different original procedures of time resolution improvement (till 1 μs) firstly showed that the simple Jovian S-bursts have an internal microstructure, which also presents some kind of DAM emission modulation. Progress in electronics, computer and information technologies allows to create the effective registration systems with high frequency and temporal resolutions (for example, Digital Signal Processors (DSP), the Waveform Receiver (WFR) and so on). Using these back-ends in connection with large radio telescope the results can be unique. Some improvements can be also reached by applying special mathematical methods. These new technologies give the possibility to found and investigate the specific features of the Jovian emission on the more high quality and quantity levels. In the present work special attention is paid on the modulation events which can be presented at the Jovian S-emission dynamic spectra in dependence on the time resolution achieved in the experiment and also on the visualization time scale. It is obvious that the dynamic spectra image is changing with the visualization time scale. The wide-band data taken for the present analysis have been obtained with the high frequency and time resolution equipment of a Digital Spectropolarimeter [Kleewein et al., 1997] and a Waveform Receiver [Leitner and Rucker, 2001] installed into the world’s largest decameter band radio telescope UTR-2 [Konovalenko et al., 2001]. The DSP provides the ultimate spectral analysis capability performing real time digital signal processing. The WFR reaches a maximum theoretically possible time-frequency resolution. The main concept of the waveform receiver is to store the signal’s original waveform. The frequency resolution of DSP is 12.5 kHz, the bandwidth is 12.5 MHz and dynamic range is 70 dB. During the experiments a time resolution was varied from 1ms to 100 ms. Complex modulation structure of the signals makes the natural difficulties for the data analysis and interpretation. In Fig.1 the consecutive zooms of one dynamic spectrum are presented. An initial spectrum was obtained with UTR-2 and DSP. The spectrum image changes with varying the time interval. It needs to be stressed that a variety of evident different scale modulation effects can be marked even for such simple example. Fig. 1 SOME OBSERVATIONAL RESULTS In the Fig.2 and Fig.3 some kind of extraordinary modulation events were presented. In the work of Ryabov, 2001 was mentioned that the long series of S-bursts are concentrated inside spectral bands with width from 1.5 to 5 MHz and a distance between central frequencies of bands in order of 3.5 MHz. Bands can have a positive and also a negative drift. During the experiments with UTR-2 and DSP the similar band structures were obtained. The high sensitive and frequency-time resolution of receiving facilities in our investigation allow to get the more specific information and, in some cases, more complex content. As an example, in Fig.2 the dynamic spectrum with clear expressed two spectral bands, containing the long series of S-bursts, is illustrated. Distance between central frequencies of bands is approx. 6 MHz, and there is not frequency drift of bands. In the spectrum a non-regular frequency modulation in each band is clearly seen. In the same time the strong correlation of large scale events and absolute absence of correlation between small scales effects in the bands is visible. The spectrum presented in the Fig.3 is also interesting due to the uncommonness: the S-burst radiation is modulated in the form of cross-lane structure consisting of spots of ~ 0.4 ms duration. The crossed-lanes demonstrate a positive and negative frequency drift simultaneously, with the faster negative drift reaching 40 MHz/sec and slow positive drift ~ 1.2 MHz/s. In Fig.4 internal structure of simple S-burst obtained by the changing visualization scale is shown. It is clear seen that burst consists of series of millisecond pulses which appear due to the complex modulation processes as in frequency as well as in time. In the Fig. 5 one more specific spectrum which consists frequency drifting consecutive quasi-harmonic structures which exist against a background of classical S-burst emission is shown. Of course, more detail investigation needs to be carried out for demonstration if this phenomenon belongs to the Jovian origin, in particular the experiments in ON-OFF regime or with distant antennas can clarify this question. Fig.3 Fig.2 Fig.5 Fig.4 CONCLUSION In the present work the wide-band dynamic spectra of the Jovian decameter emission which have been obtained during last years with the high-frequency and high-time-resolution equipment on the UTR-2 radio telescope have been analyzed. Main attention was paid to the detection and consideration of the different kinds of modulation effects, as known before and also firstly discovered. Several new intriguing kinds of spectrum modulation have been found Without any doubt the theoretical and experimental investigations of these phenomena are necessary to be continued with the largest existing instruments and with the future LOFAR and LWA. REFERENCES Riihimaa, J.J., Modulation Lanes in the Dynamic Spectra of Jupiter‘s Decametric Radio Bursts, A&A, 78, L21-L23, 1979. Genova F., M.G. Aubier, and A. Lecacheux, Modulations in Jovian Decameter Spectra: Propagation Effects in Terrestrial Ionosphere and Jovian Environment, A&A, 104, 229-239, 1981. Imai, K., L. Wang, T.D. Carr, Modeling Jupiter‘s decametric modulation lanes, JGR, 102, 7127-7136, 1997. Ryabov, B.P., Jovian Decametric Emission. Multiscale Dynamic Spectra, Radiophysics and Radioastronomy, 6, 103-130, 2001. Carr, T.D., and F. Reyes, J.Geophys.Res.-Space, 104, 127, 1999. Litvinenko, G.V., H.O. Rucker, V.V. Vinogradov, M. Leitner, and V.E. Shaposhnikov, Astron. Astrophys., 426, 343, 2004. Kleewein, P., C. Rosolen, and A. Lecacheux, New digital spectrometers for ground-based decameter radio astronomy, in: Planetary Radio Emission IV, Eds. H.O. Rucker, S.J. Bauer, and A. Lecacheux, Austrian Academy of Sciences Press, Vienna, 51, 1997. Leitner, M., and H.O. Rucker, in: Planetary Radio Emissions V, Eds. H. O. Rucker, M. L. Kaiser, Y. Leblanc, Austrian Academy of Sciences Press, Vienna, 91-96, 2001. Konovalenko, A.A., A. Lecacheux, C. Rosolen, and H.O. Rucker, ibid., 63-76, 2001.