Beaming structures of Jupiter's decametric common S-bursts observed from LWA1, NDA, and URAN2 radio telescopes

TL;DR

This study used simultaneous multi-telescope observations to analyze Jupiter's decametric S-bursts, revealing beaming characteristics and constraining the minimum beaming thickness, with implications for understanding Jupiter's radio emission mechanisms.

Contribution

First simultaneous multi-telescope measurement of Jupiter's S-bursts across multiple baselines, providing new constraints on beaming thickness and emission models.

Findings

Lag times support flashlight-like beaming model.

Minimum beaming thickness constrained to 2.66 arcseconds.

Peak S-burst occurrence at 17-18 MHz.

Abstract

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: Long Wavelength Array Station One (LWA1) in USA; Nan\c{c}ay Decameter Array (NDA) in France; and URAN2 telescope in Ukraine. We measure lag times of short-bursts (S-bursts) for 105-minutes of data over effective baselines 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 2.66". Also, we find that most of the analyzed data abound with S-bursts, whose occurrence probability peaks at 17-18 MHz.