The MASER (Measuring, Analysing and Simulating Radio Emissions) project provides a comprehensive infrastructure dedicated to low frequency radio emissions (typically < 50 to 100 MHz). The four main radio sources observed in this frequency are the Earth, the Sun, Jupiter and Saturn. They are observed either from ground (down to 10 MHz) or from space (down to a few kHz). Ground observatories are more sensitive than space observatories and capture high resolution data streams (up to a few TB per day for modern instruments). Conversely, space-borne instruments can observe below the ionospheric cut-off (10 MHz) and can be placed closer to the studied object. Several tools have been developed in the last decade for sharing space physcis data. Data visualization tools developed by the CDPP (http://cdpp.eu, Centre de Données de la Physique des Plasmas, in Toulouse, France) and the University of Iowa (Autoplot, http://autoplot.org) are available to display and analyse space physics time series and spectrograms. A planetary radio emission simulation software is developed in LESIA (ExPRES: Exoplanetary and Planetary Radio Emission Simulator). The VESPA (Virtual European Solar and Planetary Access) provides a search interface that allows to discover data of interest for scientific users, and is based on IVOA standards (astronomical International Virtual Observatory Alliance). The University of Iowa also develops Das2server that allows to distribute data with adjustable temporal resolution. MASER is making use of all these tools and standards to distribute datasets from space and ground radio instruments available from the Observatoire de Paris, the Station de Radioastronomie de Nançay and the CDPP deep archive. These datasets include Cassini/RPWS, STEREO/Waves, WIND/Waves, Ulysses/URAP, ISEE3/SBH, Voyager/PRA, Nançay Decameter Array (Routine, NewRoutine, JunoN), RadioJove archive, swedish Viking mission, Interball/POLRAD… MASER also includes a Python software library for reading raw data. This work is supported by CDPP, CNES, PADC and Europlanet-2020-RI. The Europlanet 2020 Research Infrastructure project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 654208.

The occurrence of Jovian decametric emission (DAM) is sporadic as observed from ground-based instruments. When the timing intervals of observed occurrences of Jovian DAM are compared to all periods when Jupiter was observable, a set of Jovian DAM emission occurrence probabilities can be created. These probabilities are usefully plotted as a function of Jovian system III (magnetospheric) central meridian longitude (CML-III) and Io’s phase measured from superior geocentric conjunction (SGC), producing a CML-Io phase plane. It has been known since 1964 that Jovian DAM tends to have higher occurrence probabilities in different regions of the CML-Io phase plane, leading to the identification of different Io-related and non-Io-related DAM components. AJ4CO Observatory, located in High Springs, Florida, USA, has been observing Jupiter when it is within ~4.5 hours of transit since October, 2013. The primary instrument used for observing Jovian DAM is a swept-frequency (16 to 32 MHz) dual polarization spectrograph fed by an eight-element phased array of terminated folded dipoles. A high-speed digital spectrograph with a tunable 2 MHz bandwidth was also used from 2013 to 2016 to observe emission at higher time resolution. We analyze the dynamic spectra of Jovian DAM observed at AJ4CO Observatory from 2013 through 2020 to measure emission timing intervals and classify the emission into four types: L (for wideband L bursts), S (for wideband S bursts), N (for narrowband continuous emission), and T (for narrowband trains of S bursts). For this presentation, we show CML-Io phase plane probabilities categorized by radio frequency, polarization, emission type, and emission arc shape. We show how the various high-probability DAM regions within the phase plane change with each parameter and with various combinations of parameters. We present updated definitions of the DAM component phase plane boundaries and discuss how the DAM components appearing in various parts of the CML-Io phase plane may differ from one another.