New radio observations from uGMRT (red) highlight the detailed structure of the radio relic that curves around the diffuse X-ray emission seen by the Chandra X-ray Observatory (blue). Various regions of the radio relic are labeled. Click for high-resolution version. Credit: Rajpurohit et al. 2022
Galaxy cluster Abell 2256 is home to an incredible variety of structures
traced by radio emission. The most prominent structure is an extended
radio relic: a region of diffuse radio emission found on the outskirts
of a cluster of galaxies. The precise cause of these massive radio
relics is unknown, though shocks are expected to play a central role;
the acceleration, re-acceleration, or compression of plasma by a shock
wave could all cause the observed emission. Using new deep observations
by the Giant Metrewave Radio Telescope (uGMRT) — shown above and to the
right — a team led by Kamlesh Rajpurohit (University of Bologna, Italy;
National Institute of Astrophysics, Italy; Thuringian State Observatory,
Germany) investigated the cause of the striking radio emission
surrounding Abell 2256. The new high-resolution images and spectra
suggest that the surface of the radio relic traces a shock front, which
is jumbled and twisted by interactions with the hot, turbulent plasma
that suffuses the space between the galaxies in the cluster. For more
fantastic images of the Abell 2256 radio relic, be sure to read the full
article below!
Citation
“Deep Low-frequency Radio Observations of A2256. I. The Filamentary Radio Relic,” K. Rajpurohit et al 2022 ApJ 927 80. doi:10.3847/1538-4357/ac4708
By Kerry Hensley
Source: American Astronomical Society - AAS Nova
