Spectroscopic imaging of the corona

23 August 2012. Spectroscopic imaging of the corona based on new-technology equipment - LOFAR (the LOw Frequency ARray) and solar applications
Spectroscopic imaging of the corona

LOFAR observation

The solar physicists of the Leibniz-Institut fuer Astrophysik Potsdam (AIP) observed the Sun with the novel radio telescope LOFAR in collaboration with the LOFAR team at ASTRON in the Netherlands.

Here, LOFAR's first simultaneous spectroscopic and imaging observations of a solar radio burst are presented:

Within the commissioning phase, the Sun was observed by LOFAR on October 13, 2011. At the bottom of figure #1, the dynamic radio spectrum of some minutes of the record is presented in the frequency range 122-162 MHz. It shows four so-called type III radio bursts. They appear as the rapidly drifting stripes of enhanced radio emission from high to low frequencies. They are signatures of beams of energetic electrons generated by a flare on the Sun. If they travel along open magnetic field lines through the corona, they excite along their path radio radiation manifesting as type III bursts.

Movie LOFAR obeservation

Figure #1:

More about LOFAR:

LOFAR is a novel radio telescope, which was designed by ASTRON in the Netherlands (NL) for observing the sky at low frequencies between 30 and 240 MHz with unprecedented accuracy and flexibility. The instrument is a milestone toward a new quality of radioastronomical research. Of course, LOFAR is also of great importance for solar physics.

The instrument consists of 22 core and 18 remote stations in the Netherlands, as well as eight stations in Sweden, the United Kingdom, France, and Germany. One of them was established by the AIP in Potsdam-Bornim. The radio signals of all stations are transfered using a new-technology data link of 10 Gbit/s to a powerful special computer system (Blue-Gene) in Groningen, where radio maps are calculated as a function of observing frequency and time, as well as dynamic spectral diagrams of the observations. LOFAR is operated by an European consortium, among them also the AIP.

The science with LOFAR is organized in key-science projects covering the broad interests of the community in this spectral range. The AIP is co-ordinating one of them named "Solar Physics and Space Weather with LOFAR". 31 scientists from 11 European countries joined the solar KSP.

 

Science contact: apl. Prof. Dr. Gottfried Mann, +49 331 7499 292, gmann@aip.de

Press contact: Kerstin Mork, +49 331 7499 469, presse@aip.de