Galaxy cluster Abell 2256 at 60 MHz made with LOFARLOFAR has made the first images of Abell 2256 in the frequency range of 20 to 60 MHz. What came as a surprise to scientists was that the cluster of galaxies was brighter and more complex than expected. Dr. van Weeren: ‘We think that galaxy clusters form by mergers and collisions of smaller clusters'. Abell 2256 is a prime example of a cluster that is currently undergoing a collision. The radio emission is produced by tiny elementary particles that move nearly at the speed of light. With LOFAR it is possible to study how these particles get accelerated to such speeds. ‘In particular, we will learn how this acceleration takes place in regions measuring more than 10 million light years across', says Dr. Gianfranco Brunetti from IRA-INAF in Bologna, Italy, who together with Prof. Marcus Brüggen from the Jacobs University in Bremen, coordinates the LOFAR work on galaxy clusters.
LOFAR was built by a large international consortium led by the Netherlands and which includes Germany, France, the United Kingdom and Sweden. One of the main goals of LOFAR is to survey the entire northern sky at low radio frequencies, with a sensitivity and resolution about 100 times better than what has been previously done. Scientists believe that this survey will discover more than 100 million objects in the distant Universe. ‘Soon we will start our systematic surveys of the sky that will lead to great discoveries', says Prof. Huub Röttgering from Leiden University and Principal Investigator of the "LOFAR Survey Key Project".
For more information, contact:
Dr. Reinout van Weeren, astronomer,
Leiden University and ASTRON
Tel.: +31 71 527 5864
E-mail: rvweeren@strw.leidenuniv.nl
Prof. Huub Röttgering, astronomer,
Leiden University
Tel.: +31 6 41522603
E-mail: rottgering@strw.leidenuniv.nl
Femke Boekhorst,
PR & Communication, ASTRON
Tel.: +31 521 595 204
E-mail: boekhorst@astron.nl
Link to the paper:
http://home.strw.leidenuniv.nl/~rvweeren/A2256_LBA_arx.pdf
