Highlights — Some exciting recent scientific results from our group

Astronomers obtain major clues for solving the origin of cosmic magnetism

Magnetic fields play an important role in the physics of the interstellar medium in galaxies, but they are very difficult to observe at vast distances corresponding to large look-back times in the cosmic history. An international team of astronomers led by Sui Ann Mao from the Max Planck Institute for Radio Astronomy in Bonn, Germany was able to measure the magnetic field in a galaxy beyond the local volume, as seen 4.6 billion light years away at a redshift of 0.439. The galaxy, acting as the lens in the gravitational lensing system CLASS B1152+199, is the most distant galaxy to-date in which a large-scale coherent magnetic field has been observed. This measurement provides new insights into the origin and evolution of magnetic fields in the Universe.

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

A team of astronomers led by Fatemeh Tabatabaei from the Instituto de Astrofisica de Canarias (IAC), including scientists from two Max Planck institutes (MPIfR, Bonn and MPIA, Heidelberg), has measured the radio emission for a large sample of galaxies with the Effelsberg 100-m radio telescope at different wavelengths. These galaxies were selected from the KINGFISH sample previously observed in the infrared with the Herschel satellite. This allows for the first time a comparative study of a total of 52 spiral galaxies. A reliable method could be established to determine the star formation rate exclusively from radio data without including other spectral regimes.

For the first time astronomers have exactly pinpointed the location of a "fast radio burst" - a type of short-duration radio flash of unknown astrophysical origin - and have used this to identify its home galaxy. The galaxy, located over 3 billion light years away, is small, a so-called dwarf galaxy, and very different to our own Milky Way. Also, a persistent, compact radio source is close to the source of the bursts, which provides important insights into its astrophysical origin.