Bibcode
DOI
Sambruna, Rita M.; Maraschi, L.; Tavecchio, F.; Urry, C. Megan; Cheung, C. C.; Chartas, G.; Scarpa, R.; Gambill, Jessica K.
Bibliographical reference
The Astrophysical Journal, Volume 571, Issue 1, pp. 206-217.
Advertised on:
5
2002
Journal
Citations
124
Refereed citations
103
Description
We present the first results from an X-ray and optical survey of a
sample of radio jets in active galactic nuclei with Chandra and the
Hubble Space Telescope (HST). We focus here on the first six sources
observed in X-ray, in four of which a bright X-ray jet was detected for
the first time. In three out of the four cases, optical emission from
the jet is also detected in our HST images. We compare the X-ray
morphology with the radio as derived from improved processing of
archival Very Large Array data, and we construct spectral energy
distributions (SEDs) for the most conspicuous emission knots. In most
cases, the SEDs, together with the similarity of the X-ray and radio
morphologies, favor an inverse Compton origin for the X-rays. The most
likely origin of the seed photons is the cosmic microwave background,
implying the jets are still relativistic on kiloparsec scales. However,
in the first knot of the PKS 1136-135 jet, X-rays are likely produced
via the synchrotron process. In all four cases, bulk Lorentz factors of
a few are required. The radio maps of the two jets not detected by
either Chandra or HST suggest that they are less beamed at large scales
than the other four detected sources. Our results demonstrate that, at
the sensitivity and resolution of Chandra, X-ray emission from
extragalactic jets is common, yielding essential information on their
physical properties.