Particle acceleration and magnetic field amplification in the jets of 4C74.26
Astrophysical Journal American Astronomical Society 806:2 (2015) ARTN 243
Abstract:
We model the multi-wavelength emission in the southern hotspot of the radio quasar 4C74.26. The synchrotron radio emission is resolved near the shock with the MERLIN radio-interferometer, and the rapid decay of this emission behind the shock is interpreted as the decay of the amplified downstream magnetic field as expected for small scale turbulence. Electrons are accelerated to only 0.3 TeV, consistent with a diffusion coefficient many orders of magnitude greater than in the Bohm regime. If the same diffusion coefficient applies to the protons, their maximum energy is only ~100 TeV.Multiwavelength study of Cygnus A
Astronomy & Astrophysics EDP Sciences 574 (2015) a30
Do high-redshift quasars have powerful jets?
Monthly Notices of the Royal Astronomical Society: Letters Oxford University Press (OUP) 442:1 (2014) l81-l84
Multiwavelength study of Cygnus A IV. Proper motion and location of the nucleus
ArXiv 1402.5931 (2014)
Abstract:
Context. Cygnus A, as the nearest powerful FR II radio galaxy, plays an important role in understanding jets and their impact on the surrounding intracluster medium. Aims. To explain why the nucleus is observed superposed onto the eastern lobe rather than in between the two lobes, and why the jet and counterjet are non-colinear. Methods. We made a comparative study of the radio images at different frequencies of Cygnus A, in combination with the published results on the radial velocities in the Cygnus A cluster. Results. From the morphology of the inner lobes we conclude that the lobes are not interacting with one another, but are well separated, even at low radio frequencies. We explain the location of the nucleus as the result of the proper motion of the galaxy through the cluster. The required proper motion is of the same order of magnitude as the radial velocity offset of Cygnus A with the sub-cluster it belongs to. The proper motion of the galaxy through the cluster likely also explains the non-co-linearity of the jet and counterjet.X-ray emission around the z=4.1 radio galaxy TNJ1338-1942 and the potential role of far-infrared photons in AGN Feedback
ArXiv 1307.1594 (2013)