Testing for Shock-heated X-Ray Gas around Compact Steep Spectrum Radio Galaxies
AuthorO’Dea, C. P.
Worrall, D. M.
Tremblay, G. R.
Clarke, T. E.
Baum, S. A.
Christiansen, K. P.
Mullarkey, C. A.
AffiliationUniv Arizona, Steward Observ
galaxies: individual (PKS B1017-325, B3 1445+410)
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationTesting for Shock-heated X-Ray Gas around Compact Steep Spectrum Radio Galaxies 2017, 851 (2):87 The Astrophysical Journal
JournalThe Astrophysical Journal
Rights© 2017. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractWe present Chandra and XMM-Newton X-ray, Very Large Array (VLA) radio, and optical observations of three candidate compact steep spectrum (CSS) radio galaxies. CSS sources are of a galactic scale and are presumably driving a shock through the interstellar medium (ISM) of their host galaxy. B3 1445+410 is a low-excitation emission line CSS radio galaxy with possibly a hybrid Fanaroff-Riley FRI/II (or fat double) radio morphology. The Chandra observations reveal a point-like source that is well fit with a power law consistent with the emission from a Doppler boosted core. 3C 268.3 is a CSS broad-line radio galaxy (BLRG) whose Chandra data are consistent spatially with a point source centered on the nucleus and spectrally with a double power-law model. PKS B1017-325 is a low-excitation emission line radio galaxy with a bent double radio morphology. While from our new spectroscopic redshift, PKS B1017-325 falls outside the formal definition of a CSS, the XMM-Newton observations are consistent with ISM emission with either a contribution from hot shocked gas or non-thermal jet emission. We compile selected radio and X-ray properties of the nine bona fide CSS radio galaxies with X-ray detections so far. We find that two out of the nine show X-ray spectroscopic evidence for hot shocked gas. We note that the counts in the sources are low and that the properties of the two sources with evidence for hot shocked gas are typical of the other CSS radio galaxies. We suggest that hot shocked gas may be typical of CSS radio galaxies due to their propagation through their host galaxies.
VersionFinal published version
Sponsors6.1 Base Funding; National Science Foundation; Alfred P. Sloan Foundation; National Aeronautics and Space Administration; U.S. Department of Energy; Max-Planck Society; Japanese Monbukagakusho; Higher Education Funding Council for England; NASA [NNX08AX40G, GO0-11125X, PF-150128, NAS8-03060]
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