345 citations · 1.8k across the 25 of their papers we have counts for
4 papers · 1 filter
VLBI observations of weak sources using fast frequency switching
E. Middelberg, A. L Roy, R. C. Walker +1
We have developed a new phase referencing technique for high frequency VLBI observations. In conventional phase referencing, one interleaves short scans on a nearby phase calibrato…
Modeling the 3C 120 Radio Jet from 1 to 30 Milliarcseconds
P. E. Hardee, R. C. Walker, J. L. Gomez
The predicted spatial development of helical structures along an expanding jet are used to model observed structures and motions in the 3C 120 jet. Proper motions of helical compon…
VLBI detections of a source weaker than 100 mJy at 86 GHz
E. Middelberg, A. L. Roy, R. C. Walker +1
We use a new phase-calibration strategy to calibrate the phase of 86 GHz VLBI observations of the FR I radio galaxy NGC 4261. Instead of switching between a calibrator source and t…
The X-ray Jet of 3C 120: Evidence for a Non-standard Synchrotron Spectrum
D. E. Harris, A. E. Mossman, R. C. Walker
We report on archival data from the Chandra X-ray Observatory for the radio jet of 3C120. We consider the emission process responsible for the X-rays from 4 knots using spectra con…