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

(Abridged) Radio relics in galaxy clusters are believed to be associated withpowerful shock fronts that originate during cluster mergers, and are a testbedfor the acceleration of relativistic particles in the intracluster medium.Recently, radio relic observations have pushed into the cm-wavelength domain(1-30 GHz) where a break from the standard synchrotron power-law spectrum hasbeen found, most noticeably in the famous 'Sausage' relic. In this paper, wepoint to an important effect that has been ignored or considered insignificantwhile interpreting these new high-frequency radio data, namely thecontamination due to the Sunyaev-Zel'dovich (SZ) effect that changes theobserved synchrotron flux. Even though the radio relics reside in the clusteroutskirts, the shock-driven pressure boost increases the SZ signal locally byroughly an order of magnitude. The resulting flux contamination for somewell-known relics are non-negligible already at 10 GHz, and at 30 GHz theobserved synchrotron fluxes can be diminished by a factor of several from theirtrue values. Interferometric observations are not immune to this contamination,since the change in the SZ signal occurs roughly at the same length scale asthe synchrotron emission, although there the flux loss is less severe thansingle-dish observations. We present a simple analytical approximation for thesynchrotron-to-SZ flux ratio, based on a theoretical radio relic model thatconnects the non-thermal emission to the thermal gas properties, and show thatby measuring this ratio one can potentially estimate the relic magnetic fieldsor the particle acceleration efficiency.

The impact of the SZ effect on cm-wavelength (1-30 GHz) observation of galaxy cluster radio relics