THE BEAMING STRUCTURES OF JUPITER’S DECAMETRIC COMMON S-BURSTS OBSERVED FROM THE LWA1, NDA, AND URAN2 RADIO TELESCOPES

On 2015 February 21, simultaneous observations of Jupiter's decametric radio emission between 10 and 33 MHz were carried out using three powerful low-frequency radio telescopes: the Long Wavelength Array Station One in the USA, the Nançay Decameter Array in France, and the URAN2 telescope in Ukraine. We measured the lag times of short-bursts (S-bursts) for 105 minutes of data over effective baselines of up to 8460 km by using cross-correlation analysis of the spectrograms from each instrument. Of particular interest is the measurement of the beaming thickness of S-bursts, testing if either flashlight- or beacon-like beaming is emanating from Jupiter. We find that the lag times for all pairs drift slightly as time elapses, in agreement with expectations from the flashlight-like beaming model. This leads to a new constraint of the minimum beaming thickness of 2farcs66. Also, we find that most of the analyzed data abound with S-bursts, whose occurrence probability peaks at 17–18 MHz

Erratum: “The Beaming Structures of Jupiter's Decametric Common S-bursts Observed from the LWA1, NDA, and URAN2 Radio Telescopes” (<A href="http://iopscience.iop.org/article/10.3847/0004-637X/826/2/176">2016, ApJ, 826, 176</A>)

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Concurrent Jovian S-Burst Beaming as Observed From LWA1, NDA, and Ukrainian Radio Telescopes

International audienceThis paper describes the statistical property of Jupiter's millisecond burst (S-burst) beaming for Io-related decametric (Io-DAM) sources from a ground-based radio telescope network. To do so, we performed simultaneous observations of Jovian Io-DAM S-bursts from 15 January through 4 May 2016 for a total of nine events using several radio telescopes. These radio telescopes include the Long Wavelength Array station One (LWA1) in the United States, Nançay Decameter Array (NDA) in France, and three large radio telescopes (UTR2, URAN2, and URAN3) in Ukraine. We conducted a cross-correlation analysis of the S-burst spectrograms in a frequency range of 10.5 to 33 MHz over effective baselines of up to 8,950 km. We found that the beaming of the S-bursts is formed on the flashlight-like structure within an east-west beam width of 2.75" for Io-A/C, 2.63" for Io-A', and 2.75" for Io-B/D. In parallel, the flashlight-like beam was completely filled because the results from all usable pairs of telescopes supported this model. Hence, these beam widths directly correspond to the minimum cone thickness where a radio source emanates over large solid angles from the same direction of Jupiter, as opposed to a localized radio source emitting over small solid angles along active magnetic flux tubes that are tied to Io's orbital motion in Jupiter's rotation frame (beacon-like structure). Additionally, this cross-correlation technique shows a practical benefit of producing statistical profiles of S-bursts