On the Polarisation of Radio Relics

Hoeft, M.; Rajpurohit, K.; Wittor, Denis; Gennaro, G. Di; Domínguez-Fernández, Paola

doi:10.3390/galaxies10010010

Cited by 4 publications

(2 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These findings have been used by Hoeft et al [223] to derive an analytical model for the polarised emission of radio relics. This model yields the result that the shock compression scenario indeed provides a plausible explanation for the radio relic polarisation.…”

Section: Polarisationmentioning

confidence: 98%

Cosmic-Ray Acceleration and Magnetic Fields in Galaxy Clusters and Beyond: Insights from Radio Observations

Wittor

2023

Universe

Self Cite

View full text Add to dashboard Cite

The discovery of diffuse radio emission in galaxy clusters proved the existence of energetic cosmic-ray electrons and cosmic magnetic fields on Mpc-scales in the Universe. Furthermore, both magnetic fields and cosmic-ray electrons are predicted to exist beyond galaxy clusters, namely, in the filaments and voids of the cosmic web. Recent detection of diffuse radio emission in intercluster bridges—the region between two merging clusters—strengthens the theory that both cosmic magnetic fields and cosmic-ray electrons exist on these large scales. Radio observations are our most powerful tool to study cosmic magnetic fields and cosmic-ray electrons in the Universe. The recent improvements in radio astronomy, including the exploration of the low-frequency radio sky, have led to the discovery of countless new radio sources, and hence a new understanding of the origin and evolution of cosmic magnetic fields and cosmic-ray electrons. In this contribution, we summarise the newest discoveries in the field. Furthermore, we discuss what these new radio observations teach us about cosmic magnetic fields and cosmic rays in galaxy clusters and beyond.

show abstract

Section: Polarisationmentioning

confidence: 98%

Cosmic-Ray Acceleration and Magnetic Fields in Galaxy Clusters and Beyond: Insights from Radio Observations

Wittor

2023

Universe

Self Cite

View full text Add to dashboard Cite

show abstract

“…They found that the fractional polarization is crucially affected by the magnetic field strength, which influences the decrease downstream, while the shock strength has little effect on the fractional polarization. Shock compression is a plausible scenario that can explain the radio relic polarization [10].…”

Section: Galaxy Clusters Groups and Diffuse Emissionmentioning

confidence: 99%

New Window on the Radio Emission from Galaxies, Clusters and Cosmic Web—Conference Summary

Loi

Venturi

2022

Galaxies

View full text Add to dashboard Cite

show abstract

Using the polarization properties of double radio relics to probe the turbulent compression scenario

Stuardi

Bonafede

Rajpurohit

et al. 2022

A&A

View full text Add to dashboard Cite

Context. Radio relics are megaparsec-sized synchrotron sources located in the outskirts of some merging galaxy clusters. Binarymerging systems with a favorable orientation may host two almost symmetric relics, named double radio relics. Aims. Double radio relics are seen preferentially edge-on and, thus, constitute a privileged sample for statistical studies. Their polarization and Faraday rotation properties give direct access to the relics' origin and magnetic fields. Methods. In this paper, we present a polarization and rotation measure (RM) synthesis study of four clusters hosting double radio relics, namely 8C 0212+703, Abell 3365, and PLCK G287.0+32.9; previously missing polarization studies; and ZwCl 2341+0000, for which conflicting results have been reported. We used 1-2 GHz Karl G. Jansky Very Large Array observations. We also provide an updated compilation of known double radio relics with important observed quantities. We studied their polarization and Faraday rotation properties at 1.4 GHz and we searched for correlations between fractional polarization and physical resolution, the distance from the cluster center, and the shock Mach number. Results. The weak correlations found between these quantities are well reproduced by state-of-the-art magneto-hydrodynamical simulations of radio relics, confirming that merger shock waves propagate in a turbulent medium with tangled magnetic fields. Both external and internal Faraday depolarization should play a fundamental role in determining the polarization properties of radio relics at 1.4 GHz. Although the number of double radio relics with RM information is still low, their Faraday rotation properties (i.e., restframe RM and RM dispersion below 40 rad m −2 and non-Gaussian RM distribution) can be explained in the scenario in which shock waves with Mach numbers larger than 2.5 propagate along the plane of the sky and compress the turbulent intra-cluster medium.

show abstract

On the Polarisation of Radio Relics

Cited by 4 publications

References 21 publications

Cosmic-Ray Acceleration and Magnetic Fields in Galaxy Clusters and Beyond: Insights from Radio Observations

Cosmic-Ray Acceleration and Magnetic Fields in Galaxy Clusters and Beyond: Insights from Radio Observations

New Window on the Radio Emission from Galaxies, Clusters and Cosmic Web—Conference Summary

Using the polarization properties of double radio relics to probe the turbulent compression scenario

Contact Info

Product

Resources

About