A new high-grain, broadband, steerable array to study Jovian decametric emission

We study the characteristics of moving type IV radio bursts which extend to the hectometric wavelengths (interplanetary type IV or type IV IP bursts) and their relationship with energetic phenomena on the Sun. Our dataset comprises 48 interplanetary type IV bursts observed with the Radio and Plasma Wave Investigation (WAVES) instrument onboard Wind in the 13.825 MHz-20 kHz frequency range. The dynamic spectra of the Radio Solar Telescope Network (RSTN), the Nançay Decametric Array (DAM), the Appareil de Routine pour le Traitement et l' Enregistrement Magnetique de l' Information Spectral (ARTEMIS-IV), the Culgoora, Hiraiso and Izmiran Radio Spectrographs were used to track the evolution of the events in the low corona. These were supplemented with soft X-ray (SXR) flux-measurements from the Geostationary Operational Environmental Satellite (GOES) and coronal mass ejections (CME) data from the Large Angle and Spectroscopic Coronagraph (LASCO) onboard the Solar and Heliospheric Observatory (SOHO). Positional information of the coronal bursts was obtained by the Nançay radioheliograph (NRH). We examined the relationship of the type IV events with coronal radio bursts, CMEs and SXR flares. The majority of the events (45) were characterized as compact; their duration was on average 106 minutes. This type of events was, mostly, associated with M-and X-class flares (40 out of 45) and fast CMEs; 32 of these events had CMEs faster than 1000 km s −1 . Furthermore, in 43 compact events the CME was, possibly, subjected to reduced aerodynamic drag as it was propagating in the wake of a previous CME. A minority (three) of long lived type IV IP bursts was detected, with duration from 960 minutes to 115 hours. These events are referred to as extended or long duration and appear to replenish their energetic electron content, possibly from electrons escaping from the corresponding coronal type IV bursts. The latter were found to persist on the disk, for tens of hours to days. Prominent among them was the unusual interplanetary type IV burst of 18-23 May 2002, which is the longest event in the Wind /WAVES catalog. The three extended events were, usually, accompanied by a number of flares, of GOES class C in their majority, and of CMEs, many of which were slow and narrow.

show abstract

“…• The Nançay Decametric Array or DAM 3 (Boischot et al, 1980;Lecacheux, 2000, observes in the range 20-75 MHz. ).…”

Section: Observations and Data Selectionmentioning

confidence: 99%

Interplanetary Type IV Bursts

2016

View full text Add to dashboard Cite

show abstract

“…The Nançay decameter array (NDA) has operated since 1977, routinely observing Jupiter's decametric radio emissions (Boischot et al 1980). The NDA is a phased array consisting of 144 helix conical log-periodic antennas: 72 sensitive to RH circular polarization and 72 to LH polarization.…”

Section: Html)mentioning

confidence: 99%

Solar wind effects on Jupiter non-Io DAM emissions during Ulysses distant encounter (2003–2004)

Echer

Zarka

González

et al. 2010

A&A

View full text Add to dashboard Cite

Aims. We analyze solar wind data from the Ulysses spacecraft during the distant Jupiter encounter from 2003 November to 2004 March as well as Nançay decametric (DAM) radio observations non-controlled by Io. Methods. The Ulysses solar wind data are balistically propagated towards Jupiter and are correlated with Nançay non-Io DAM emissions. Results. It is found that the average solar wind dynamic pressure around the time of DAM emissions is 1.7 times higher than its average value during the Ulysses encounter. The occurrence of fast forward (FS) and reverse (RS) interplanetary shocks and heliospheric current sheet crossings (HCS) is correlated with the occurrence of non-Io DAM emissions. We note an enhanced probability of occurrence of non-Io DAM emissions after the expected arrival of FS, RS and HCS at Jupiter. However, about half emissions (54%) did not seem to be associated with these interplanetary structures. We also note that the average duration and power of non-Io DAM emissions are enhanced during periods associated with those interplanetary structures. Conclusions. From the results obtained in this work it seems that non-Io DAM emissions occur during intervals of enhanced solar wind dynamic pressure. Yet, there is no direct correlation between the non-Io DAM emissions duration or power versus the solar wind pressure values and the interplanetary shock Mach number.

show abstract

“…We combine here data from the WAVES experiment on the Wind spacecraft [Bougeret et al, 1995] and from the Nanvay Decameter Array [Boischot et al, 1980], which provide to- gether a continuous coverage of the range 1-40 MHz, allowing us to study arc shapes over their entire frequency range (3 to 37.5 MHz, see Table 1). …”

Section: Radio Observationsmentioning

confidence: 99%

Io‐controlled decameter arcs and Io‐Jupiter interaction

Queinnec¹,

Zarka²

1998

J. Geophys. Res.

138

View full text Add to dashboard Cite

Abstract. The motion of the satellite Io in Jupiter's magnetic field results in an electrodynamic circuit, approximately fixed in Io's frame, revealed by ultraviolet and infrared spots at the footprints of Io's flux tube (IFT) as well as prominent (so-called "Io-controlled") decameter radio arcs. We analyze the frequency-time shape of nine such arcs, corresponding to four observation geometries (A,B,C,D) and detected over their full frequency extent in joint Nanqay and Wind data. We compute the radio beaming angle as a function of frequency and lag of the radio-emitting flux tube(s) relative to the IFT. No a priori assumption is made regarding the radio source beaming, and its location is only constrained by the emission occurring near the local electron gyrofrequency. We find northern sources for A and B arcs and southern sources for C and D arcs. The shape of all Io arcs is consistent with an origin at a single flux tube (in Io's frame), shit•ed by an average of 10 ø (in the south) and 25 ø (in the north) with respect to the IFT. This lag must be accumulated before Io's magnetic perturbation reaches the radio emission region, at high latitudes, at altitudes 5 1 R• above the Jovian surface. Radio emission is found to be beamed in a hollow cone of average half-apex angle 70ø-75 ø and thickness --1 ø. Arc shapes are fully determined by the geometry of observation. Radio fringes preceding the main Io B arcs are well explained by multiple reflections of the magnetic perturbation between Jupiter's ionosphere and Io's torus. The weak trailing part of Io-B arcs may be accounted for through double beaming of the radio emission or through a frequency-dependent lag of the corresponding radio source. The latter explanation suggests an emission scenario in which electron acceleration "leaks" from the magnetic perturbation on its way to Jupiter. Jovian magnetic field models are compared and evaluated in the analysis.

show abstract

A new high-grain, broadband, steerable array to study Jovian decametric emission

Cited by 117 publications

References 4 publications

Interplanetary Type IV Bursts

Interplanetary Type IV Bursts

Solar wind effects on Jupiter non-Io DAM emissions during Ulysses distant encounter (2003–2004)

Io‐controlled decameter arcs and Io‐Jupiter interaction

Contact Info

Product

Resources

About