VLA reveals distant galaxy's magnetic field
National Radio Astronomy Observatory
The achievement is giving them important new clues about a problem at the frontiers of cosmology – the nature and origin of the magnetic fields that play an important role in how galaxies develop over time. The polarization of the waves coming from the background quasar, combined with the fact that the waves producing the two lensed images traveled through different parts of the intervening galaxy, allowed us to learn some important facts about the galaxy’s magnetic field, said Sui Ann Mao, Minerva Research Group Leader for the Max Planck Institute for Radio Astronomy in Bonn, Germany. Analysis of the VLA images showed a significant difference between the two gravitationally-lensed images in how the waves’ polarization was changed. The results of our study support the idea that galaxy magnetic fields are generated by a rotating dynamo effect, similar to the process that produces the Sun’s magnetic field, Mao said. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.