135 citations · 517 across the 16 of their papers we have counts for
7 papers · 1 filter
Structure and Magnetic Fields in the Precessing Jet System SS 433 I. Multi-Frequency Imaging from 1998
David H. Roberts, John F. C. Wardle, Scott L. Lipnick +2
The Very Large Array has been used at five frequencies to study the structure and linear polarization of SS433 on scales as small as ~0.1" ~ 500 AU. Each jet consists of a sharp, c…
Multi-Frequency VSOP and VLBA Polarization Observations of 3C279 and 3C345
C. C. Cheung, D. H. Roberts, J. F. C. Wardle +2
This contribution presents preliminary results from coordinated polarization sensitive VSOP and VLBA imaging of the blazars 3C~279 and 3C~345 at multiple frequencies.
Parsec-Scale Blazar Monitoring: Flux and Polarization Variability
Daniel C. Homan, Roopesh Ojha, John F. C. Wardle +4
We present analysis of the flux and polarization variability of parsec scale radio jets from a dual-frequency, six-epoch, VLBA polarization experiment monitoring 12 blazars. The ob…
Making Movies from Radio Astronomical Images with AIPS
C. C. Cheung, D. C. Homan, J. F. C. Wardle +1
We present a detailed recipe for making movies from multi-epoch radio observations of astronomical sources. Images are interpolated linearly in time to create a smooth succession o…
Parsec-Scale Blazar Monitoring: Proper Motions
D. C. Homan, R. Ojha, J. F. C. Wardle +4
We present proper motions obtained from a dual frequency, six-epoch, VLBA polarization experiment monitoring a sample of 12 blazars. The observations were made at 15 GHz and 22 GHz…
Radio Jet-Ambient Medium Interactions on Parsec Scales in the Blazar 1055+018
Joanne M. Attridge, David H. Roberts, John F. C. Wardle
As part of our study of the magnetic fields of AGN we have recently observed a large sample of blazars with the Very Long Baseline Array. Here we report the discovery of a striking…
Evidence for Ordered Magnetic Fields in the Quasar Environment
P. S. Udomprasert, G. B. Taylor, T. J. Pearson +1
At a distance of 20 pc from the purported supermassive black hole powering quasars, temperatures and densities are inferred from optical observations to be ~10**4 K and ~10**4 cm**…