Contacts :
R. Romagnan
A. Hamini
S. Masson


  • NRH
  • Artemis
  • DAM
  • Wind/Waves
  • Stereo/Waves
  • Ynao
  • Humain : Callisto, ARCAS & HSRS
  • Gauribidanur
  • Culgoora
  • Learmonth

  •    NRH Nancay Radioheliograph (NRH) operated by the Observatoire de Paris and funded by the French research agency CNRS/INSU. (for a detailed description, see A. Kerdraon & Delouis, 1997).
    Contact person: L. Klein

       The NRH, located at longitude 2 degrees east, latitude 47 degrees north, consists in 44 antennas with sizes in the range 2-10m, along two arrays in the EW and NS directions. The EW and NS baselines are range from roughly 50 to 3200 m and 2440 m respectively. The NRH observes the sun about 7h per day, at several frequencies between 150 and 450 MHz. The standard observing mode consists in obtaining complex visibilities in Stokes I and V at 6 (before May 2008) then 10 frequencies (after May 2008), each 125 (resp. 250) msec.

    Two-dimensional (2D) snapshot images with time resolution 10 sec and 120 sec are routinely produced. Their resolution depends on the frequency and the season and does not correspond to the full length of the arrays, because of the incomplete filling of the uv-plane. The resolution is about 6 arcmin at 150 MHz and 2 arcmin at 450 MHz during summer, and is up to 3 times larger for the NS direction in winter. One-dimensional (1D) snapshot images in the EW and NS direction are also routinely produced, with spatial resolution 2-3 times better than for 2D snapshot image.s

    Two-dimensional images by rotational synthesis have also been produced at the same frequencies by using rotational synthesis. This has not been done systematically, but for about 220 days in summer between 2004 and 2013.

    A. Kerdraon & J. M. Delouis, Coronal Physics from Radio and Space Observations; Proceedings of the CESRA Workshop held in Nouan le Fuzelier, France 3-7 June 1996, edited by Gerard Trottet, Published by Springer, 1997, p.192

       ARTEMIS IV Multichannel solar radiospectrograph operated by the University of Athens, located at Thermopyle Satellite Station, Greece (for a complete description, see Caroubalos et al., 2001)
    Contact persons : For ARTEMIS Spectra : P. Preka-Papadema or Alexander Hillaris or Xenophon Moussas
    Scientific team : Xenophon Moussas, Costas Caroubalos, Giota Preka-Papadema, Athanasios Kontogeorgos, Panagiotis Tsitsipis, Alexander Hillaris
    Costas Alissandrakis

       ARTEMIS is located at longitude 22. 41 degrees east, latitude 38.47 north. Observations cover the frequency range from 20 to 650 MHz. The spectrograph has a 7-meter steerable parabolic antenna for 110 to 650 MHz and a fixed antenna for the 20 to 110 MHz. There are two receivers operating in parallel, one sweep frequency for the whole range (10 spectrums/sec, 630 channels/spectrum) and one acousto-optical receiver for the range 270 to 470 MHz (100 spectrums/sec, 128 channels/spectrum). The data acquisition system consists in two PCs (equipped with 12 bit, 225 ksamples/sec DAC, one for every receiver) ,Windows operating system, connected through Ethernet. The daily operation is fully automated: pointing the antenna to the sun, starting and stopping the observations at preset times, data acquisition, and archiving on DVD. The whole system can be remotely controled.

    C. Caroubalos, D. Maroulis, N. Patavalis, J-L. Bougeret, G. Dumas, C. Perche, C. Alissandrakis, A. Hillaris, X. Moussas, P. Preka-Papadema, A. Kontogeorgos, P. Tsitsipis, G. Kanellakis.: The New Multichannel Radio spectrograph ARTEMIS-IV/HECATE, of the University of Athens. Experimental Astronomy 11: 23-32, 2001.

       Nancay Decameter Array operated by the Observatoire de Paris and funded by the French research agency CNRS/INSU. (for a detailed description, see A. Lecacheux, 2000)
    Contact person: Contact

       The DAM, located at longitude 2 degrees east, latitude 47 north, operating in the 10-80 MHz frequency range, consists in two phased antenna arrays in opposite senses of circular polarisation with a 4000 m2 effective aperture each, and a set of receivers allowing for wide band, high resolution and sensitive spectroscopy of Jovian and solar radio emissions. Each array includes 72 antenna.

    A. Lecacheux Radio Astronomy at Long Wavelengths, tutorials and reviews from an AGU Chapman conference held Oct. 1998 in Paris, France. Geophysical monograph Series, Vol. 119. ISSN 0065-8448. Edited by R.G. Stone, K.W. Weiler, M.L. Goldstein, and J.-L. Bougerot. Washington, DC: American Geophysical Union, 2000., p.321

       ORFEES radiospectrograph
    Contact persons: L. Klein, A. Hamini, G. Auxepaules

       The ORFEES radio-spectrograph (Observations Radio pour Fedome et l’Etude des Eruptions Solaires) is the result of a partnership between the Paris Observatory and the Air Force French. It is dedicated to the observation of the solar corona between 144MHz and 1000MHz. The ORFEES radio-spectrograph is located at longitude 2°11’29 East and latitude 47°22'51 North. Based on a new type of digital receiver (Roach 1 map from the University of Berkeley, USA), the first observations were made in the spring of 2012.

       ORFEES has a parabolic dish of diameter 5 m and log-periodic dipoles array. The spectral domain is separated into five bands of 170 MHz. Ten spectra are recorded per second (total intensity, horizontal and vertical polarization). The radio telescope is operated automatically and tracks the Sun from ~8:00 till ~16:00 UT every day.

       The instrument characteristics are the following:

    Type of telescopeEquatorial
    Antenna Diameter5m
    Polarisation2x linear (horizontal and vertical)
    Frequency range144MHz-1000MHz
    Number of sub-bands5
    Number of channels2048
    Channel width97.65KHz
    DataStokes I & V
    Time Resolution100ms
    Observation time8h
    Data typeFITS
    Data size2.7Gb

       WAVES The Radio and Plasma Wave Investigation on the WIND Spacecraft (for a detailed description see Bougeret et al., 1995)
    Contact persons: M. Maksimovic, R. MacDowall

       The WAVES instrument is a joint effort of the Paris-Meudon Observatory, the University of Minnesota, and the Goddard Space Flight Center (NASA).
       The sensors are: (1) three electric dipolar antenna systems supplied by Fairchild Space (two are coplanar, orthogonal wire dipole antennas in the spin-plane, the other a rigid spin-axis dipole) and (2) three magnetic search coils mounted orthogonally (designed and built by the University of Iowa). After preamplification, the sensor outputs are routed to the analysis electronics, consisting in a low frequency (DC - 10 kHz) FFT receiver, a broadband (4 kHz - 256 kHz) multi-channel analyzer designed principally to study the electron thermal noise, two dual radio receivers covering the band 20 kHz to 13.825 MHz, and a time-domain waveform sampler (sampling to 120,000/s). The experiment is controlled by a central microprocessor (DPU) which can be used in flight to reconfigure the sensor outputs and to maximize the science return for the bit rate and power allotments that are available. A DC/DC power converter is also part of the electronics stack.

       The web page includes the data from the two Radio Receivers RAD1 and RAD2 whose the characteristics are the following ones:

    - Band 1 (RAD1) Inputs: Ex+Ez, Ez Frequency range: 20 kHz - 1,040 kHz No. channels: 256 Bandwidth:3 kHz Sensitivity: 7 nV/Sqrt(Hz)
    - Band 2 (RAD2) Inputs: Ey+Ez, Ez Frequency range: 1.075 MHz - 13.825 MHz No. channels: 256 Bandwidth: 20 kHz Sensitivity: 7 nV/Sqrt(Hz)

    Bougeret, J.-L.,M. L. Kaiser, P.J. Kellog et al., WAVES: the radio and Plasma Wave Investigation, Space SCi. Rev., 71, 5, 1995

        SWAVES The Radio and Plasma Wave Investigation on the STEREO mission ( for a detailed description see Bougeret et al., 2008)
    Contact persons: M. Maksimovic, R. MacDowall

    The SWAVES experiment includes the following instruments and components : (1) Radio receivers (HFR and LFRhi) that measure radio wave intensity, source direction, and angular size in the frequency range of 16 MHz to 40 kHz, corresponding to source distances of about 1 RS to 1 AU. (2) Low Frequency Receivers (LFRlo) that make sensitive measurements of radio and plasma waves near the electron plasma frequency at 1 AU (10-40 kHz). (3) A Fixed Frequency Receiver (FFR) that measures radio emissions at 50 MHz, at high time resolution, to complement ground-based radioheliograph measurements. (4) Time Domain Samplers (TDS) that simultaneously make wideband waveform measurements on 3 electric at one of several commandable sample rates and bandwidths.
    Antenna systems include three mutually orthogonal 6-meter monopoles on each STEREO spacecraft. A Data Processing Unit (DPU) on each spacecraft controls and coordinates the various instrument components and performs digital signal processing.

       The web page includes the data from one band of the LFR (40 kHz to 160 kHz) and the whole range of HFR (125 kHz to 16 MHz).

    The following table summarizes the main characteristics of the concerned receivers.

    Band C from LFRHFR
    Frequency coverage40 kHz - 160kHz125kHz - 16.025 MHz
    Frequency resolutionΔF/Fo = 8.66% >=< 50kHz
    Dynamic range120dB80dB

    J.L. Bougeret, K. Goetz, M.L. Kaiser et al. The radio and plasma wave investigation on the STEREO mission,Space Science Reviews, Vol 136, issue 1-4, 2008.

        Solar radio spectrometer of Yunnan Observatories
    Contact person: G. Gao

    The metric solar radio spectrometer is located in Fuxian Solar Observatory (102°.57 E, 24°.34 N) of Yunnan Observatories (YNAO). The spectrometer includes a 11-meter meshed parabolic antenna and a digital FFT spectrometer . The working frequency range is 70-700 MHz (see Gao et al. 2014).

    Parameters of YNAO metric spectrometer

    Frequency range70-700 MHz
    Antenna11-m meshed parabolic
    Highest spectral resolution200 kHz
    Time cadence 80ms
    Dynamic range72 dB (Maximum)
    Recording time00:00-10:00 UT
    Sensitivity~ 1 SFU
    Polarization modeleft and right circular polarization

       Spectrographs in Humain
    Contact person: C. Marque

    Observations from Humain (Belgium)
    The Humain Radioastronomy station (05° 15 12 E, 50°11 31 N), is located about 120 km to the South East of Brussels in the Belgian Ardennes.
    A 6-m dish radio telescope is operated automatically and tracks the Sun from ~7:30 till ~16:00 UT every day.
    Three spectrographs are currently installed.
  • One is a Callisto spectrograph from the e-Callisto network. It covers the band 45 - 447 MHz. The Callisto spectrograph is connected to a log-periodic antenna mounted as piggy bag on the side of the dish.
  • One, named HSRS is a SDR-based instrument used as a spectrograph. It covers the band 275 - 1495 MHz. The HSRS instrument is connected to a log-periodic antenna placed at the focus of the parabolic dish.i
  • ARCAS is a digital spectrometer based on a Software Defined Radio receiver configured to scan the band 45 - 450 MHz. It has been set up on October 27 2016, in parallel to the Callisto receiver already in operation. Both instruments share the same receiving antenna via a splitter.

  • The instruments characteristics are the following:

    Frequency range45 - 447 MHz275 - 1495 MHz45 - 450 MHz
    Frequency resolution63 kHz98 kHz98 kHz
    Number of points in frequency200~ 12500~ 4.2 k
    Time resolution0.25 s0.25 s84 ms


       Gauribidanur Low-frequency Solar Spectrograph (GLOSS)
    Contact persons:
    R. Ramesh

    Gauribidanur Low-frequency Solar Spectrograph (GLOSS) is operated by the Indian Institute of Astrophysics at the Gauribidanur radio observatory, about 100 km north of Bangalore. GLOSS is a dedicated instrument for obtaining dynamic spectrum of the transient emission from the solar corona. The antenna system consists of 8 log periodic dipoles (LPD).

    Frequency range40 - 440 MHz
    Number of frequency points401
    Spectral resolution1 MHz
    Sweep time (40 - 440 MHz)250 ms
    Observation duration02:30 to 11:30 UT (9 hr)
    Location77° E 14° N

    Reference: Gauribidanur Low-frequency Solar Spectrograph P. Kishore, C. Kathiravan, R. Ramesh, M. Rajalingam, Indrajit V. Barve, 2014, Solar Physics, Vol. 289, pp. 3995-4005

       Culgoora spectrograph

        Learmonth spectrograph