English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present new Chandra X-ray and Giant Meterwave Radio Telescope (GMRT) radioobservations of the nearby merging galaxy cluster Abell 754. Our X-ray dataconfirm the presence of a shock front by obtaining the first direct measurementof a gas temperature jump across the X-ray brightness edge previously seen inthe imaging data. A754 is only the fourth galaxy cluster with confirmed mergershock fronts, and it has the weakest shock of those, with a Mach numberM=1.57+0.16-0.12. In our new GMRT observation at 330 MHz, we find that thepreviously-known centrally located radio halo extends eastward to the positionof the shock. The X-ray shock front also coincides with the position of a radiorelic previously observed at 74 MHz. The radio spectrum of the post-shockregion, using our radio data and the earlier results at 74 MHz and 1.4 GHz, isvery steep. We argue that acceleration of electrons at the shock front directlyfrom thermal to ultrarelativistic energies is problematic due to energyarguments, while reacceleration of preexisting relativistic electrons is moreplausible.

A shock front in the merging galaxy cluster Abell 754: X-ray and radio observations