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We present recent developments of the ARTEMIS IV solar radio spectrograph operating at Thermopylae, central Greece. Observations are obtained daily in total intensity and in the frequency range from 20 to 650 MHz, using two antennas and two receivers. We are now in the process of developing a new system that will record consecutively the intensity of right-hand and left-hand polarized waves using one of the antennas and the same receivers. © Springer Science+Business Media B.V. 2008.

We analyse of a set of radio rich (accompanied by type IV or II bursts) solar flares and their association with SOHO/LASCO Coronal Mass Ejections in the period 1998-2000. The intensity, impulsiveness and energetics of these events are investigated. We find that, on the average, flares associated both with type IIs and CMEs are more impulsive and more energetic than flares associated with type IIs only (without CME reported), as well as flares accompanied by type IV continua but not type II shocks. From the last two classes, flares with type II bursts (without CMEs reported) are the shortest in duration and the most impulsive. © 2005 COSPAR.

Fine structure of type IV radio solar bursts with a great variety and complexity often give much information in different ways and enable estimation of various coronal characteristics. In this work, we expose our new method for fine structure revealing and separation of two basic kinds of type IV fine structure, as fibers and pulsations. We also estimate frequency drift of fibers from dynamic spectra, clean from continuous background, with a prototype method using 2-D Fourier transform and we estimate periodicities of fibers as well as pulsations with continuous wavelet transform. Working with the last method we found periodicities close to 3 min umbral oscillations and 5 min global solar oscillations. © Springer 2006.

We present the new solar radiospectrograph of the University of Athens operating at the Thermopylae Station since 1996. Observations cover the frequency range from 110 to 688 MHz. The radiospectrograph has a 7-meter parabolic antenna and two receivers operating in parallel. One is a sweep frequency receiver and the other a multichannel acousto-optical receiver. The data acquisition system consists of a front-end VME based subsystem and a Sun Sparc-5 workstation connected through Ethernet. The two subsystems are operated using the VxWorks real-time package. The daily operation is fully automated: pointing of the antenna to the sun, starting and stopping the observations at pre-set times, data acquisition, data compression by 'silence suppression', and archiving on DAT tapes. The instrument can be used either by itself to study the onset and evolution of solar radio bursts or in conjunction with other instruments including the Nançay Decametric Array and the WIND/WAVES RAD1 and RAD2 low frequency receivers to study associated interplanetary phenomena.