LESIA Observatoire de Paris-PSL CNRS vopdc cdpp Sorbonne Université cnes Université de Paris

Cassini/RPWS/HFR LESIA/Kronos N3b Data Collection V1.0

Wednesday 17 February 2021, by Baptiste Cecconi

This collection is composed of Cassini/RPWS/HFR (Radio and Plasma Waves Science / High Frequency Receiver) hourly N3b (Level 3b) files.

This collection is part of the Cassini/RPWS/HFR LESIA/Kronos Collection(https://doi.org/10.25935/1SXH-AQ56).

Link to data repository

The files are available from the LESIA/Kronos data repository (link below). The repository file hierarchy and the link with the other LESIA/Kronos collection are described in Cecconi et al. (2021).


The data collection contains hourly Level 3b goniopolarimetric binary files, derived from the High Frequency Receiver (HFR) of Cassini/RPWS (Radio and Plasma Waves Science) dataset. This data collection has been produced following the "full 3-antenna mode" goniopolarimetric Inversion described in section 2.1.1 of Cecconi and Zarka (2005).


The collection is composed of 140,344 binary files (68.61 GB) containing data as described in the table below.

N3b data record descriptions
ydh long 1 yyyydddhh of current file
num long 2 indices of the pair of records in current file
S float 2 V^2/m^2/Hz Spectral flux density
Q float 2 Normalized linear polarization degree Q
U float 2 Normalized linear polarization degree U
V float 2 Normalized circular polarization degree V
th float 1 deg Source colatitude (in S/C frame)
ph float 1 deg Source Azimuth (in S/C frame)
zr float 1 ratio of 2 Azz values (Azz+-Azz-)/(Azz++Azz-)
SNR float 4 dB S/N Ratio on autocorrelation values

The total length of a single record is R = 72 bytes.

The file naming convention is: N3b_XYY_yyyyddd.hh

  • X: a 1-letter code for the calibration in use.
  • YY: a 2-letter code for the radio source location assumption.
  • yyyy: Year in 4 digits
  • ddd: Day of year in 3 digits (0-padded)
  • hh: Hour of day in 2 digits (0-padded)

The file is composed of a raw series of N3b records (no header). Hence, the length of the file is equal to the number of records in file (N) multiplied by the length of a single record (R).

Coverage and sampling

  • Time range: 1998 to 2017
  • Time resolution: 30 seconds to 2 minutes.
  • Spectral range: 3.5 kHz to 16.1 MHz


The Cassini/RPWS/HFR N3b data collection has been produced by B. Cecconi, L. Lamy & P. Zarka, from the Observatoire de Paris/LESIA Cassini-RPWS team, with the support of CNRS and CNES.


Any question or request should be addressed to contact.maser@obspm.fr


  • Cecconi, B, and P Zarka. 2005. "Direction Finding and Antenna Calibration Through Analytical Inversion of Radio Measurements Performed Using a System of 2 or 3 Electric Dipole Antennas." Radio Sci., 40:RS3003. doi:10.1029/2004RS003070.
  • Cecconi, B, P Zarka, L Lamy, D Vogl and G Boisnard. 2021 "CASSINI-RPWS-HFR LESIA/Kronos Database at Obs.Paris-PSL (Meudon)". V1.8. doi:10.25935/j7br-f293