The Open UniversitySkip to content
 

A representative survey of the dynamics and energetics of FRII radio galaxies

Ineson, J.; Croston, J. H.; Hardcastle, M. J. and Mingo, B. (2017). A representative survey of the dynamics and energetics of FRII radio galaxies. Monthly Notices of the Royal Astronomical Society, 467(2) pp. 1586–1607.

Full text available as:
[img]
Preview
PDF (Version of Record) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (1MB) | Preview
DOI (Digital Object Identifier) Link: https://doi.org/10.1093/mnras/stx189
Google Scholar: Look up in Google Scholar

Abstract

We report the first large, systematic study of the dynamics and energetics of a representative sample of Fanaroff–Riley type II (FR II) radio galaxies with well-characterized group/cluster environments. We used X-ray inverse-Compton and radio synchrotron measurements to determine the internal radio-lobe conditions, and these were compared with external pressures acting on the lobes, determined from measurements of the thermal X-ray emission of the group/cluster. Consistent with previous work, we found that FR II radio lobes are typically electron dominated by a small factor relative to equipartition, and are overpressured relative to the external medium in their outer parts. These results suggest that there is typically no energetically significant proton population in the lobes of FR II radio galaxies (unlike for FR Is), and so for this population, inverse-Compton modelling provides an accurate way of measuring total energy content and estimating jet power. We estimated the distribution of Mach numbers for the population of expanding radio lobes, finding that at least half of the radio galaxies are currently driving strong shocks into their group/cluster environments. Finally, we determined a jet power–radio luminosity relation for FR II radio galaxies based on our estimates of lobe internal energy and Mach number. The slope and normalization of this relation are consistent with theoretical expectations, given the departure from equipartition and environmental distribution for our sample.

Item Type: Journal Item
Copyright Holders: 2017 The Authors
ISSN: 1365-2966
Project Funding Details:
Funded Project NameProject IDFunding Body
Not SetST/M001326/1STFC (Science & Technology Facilities Council)
Keywords: galaxies: active; galaxies: clusters: intracluster medium; galaxies: jets
Academic Unit/School: Faculty of Science, Technology, Engineering and Mathematics (STEM) > Physical Sciences
Faculty of Science, Technology, Engineering and Mathematics (STEM)
Research Group: Astronomy
Related URLs:
Item ID: 57848
Depositing User: Judith Croston
Date Deposited: 06 Dec 2018 14:21
Last Modified: 24 May 2019 06:17
URI: http://oro.open.ac.uk/id/eprint/57848
Share this page:

Metrics

Altmetrics from Altmetric

Citations from Dimensions

Download history for this item

These details should be considered as only a guide to the number of downloads performed manually. Algorithmic methods have been applied in an attempt to remove automated downloads from the displayed statistics but no guarantee can be made as to the accuracy of the figures.

Actions (login may be required)

Policies | Disclaimer

© The Open University   contact the OU