Related papers: Radio Circular Polarization Produced in Helical Ma…
The magnetic field morphology of relativistic jets can be studied with circular polarization (CP). Recent 3D relativistic magnetohydrodynamic (RMHD) simulations coupled with radiative transfer calculations make strong predictions about the…
We present the results of parsec-scale circular polarization (CP) measurements based on VLBA data for a number of radio-bright, core-dominated AGN obtained simultaneously at 15, 22 and 43 GHz. The degrees of CP $m_c$ for the VLBI core…
Many compact radio sources like quasars, blazars, radio galaxies, and micro-quasars emit circular polarisation (CP) with surprising temporal persistent handedness. We propose that the CP is caused by Faraday conversion of linear…
We report first-epoch circular polarization results for 133 active galactic nuclei in the MOJAVE program to monitor the structure and polarization of a flux limited sample of extra-galactic radio jets with the VLBA at 15 GHz. We found…
We present five epochs of 15 GHz VLBA observations of 13 AGN. These observations were specially calibrated to detect parsec scale circular polarization and our calibration techniques are discussed and analyzed in detail. We obtained…
Previously, a multi-wavelength (2cm, 4cm and 6cm) polarization study by Gabuzda, Murray and Cronin (2004) showed systematic Faraday Rotation gradients across the parsec-scale jets of several BL Lac objects, interpreted as evidence for…
We present maps of the sign of the Faraday Rotation measure [sign(RM)] obtained from multi-frequency radio observations on the Very Long Baseline Array (VLBA). Many of the Active Galactic Nuclei (AGN) considered have B-field structures with…
We propose that the interaction between the axionlike particles (ALPs) and photons can be a possible origin of optical circular polarization (CP) in blazars. Given that there is no definite detection of optical CP at $\sim0.1\%$ level, a…
Multi-frequency (4.6, 5, 5.5, 8, 8.8, 13, 15, 22 & 43 GHz) polarization observations of 6 "blazars" were obtained on the American Very Long Baseline Array (VLBA) over a 24-hr period on 2 July 2006. Observing at several frequencies,…
We present full-Stokes radio polarization observations of the quasar PKS B2126-158 (z=3.268) from 1 to 10 GHz using the Australia Telescope Compact Array. The source has large fractional circular polarization, m_c \equiv |V|/I, detected at…
One possible origin for polarization structures across jets of Active Galactic Nuclei (AGNs) with a central "spine" of orthogonal magnetic field and a "sheath" of longitudinal magnetic field along one or both edges of the jet is the…
We present circular polarization results from a 5 GHz survey of the parsec-scale polarization properties of 40 AGN made with the VLBA. We find 11 circular polarization detections at the 3 sigma level or higher. This nearly quadruples the…
We report the first detection of linearly polarized emission at an observing wavelength of 350 $\mu$m from the radio-loud Active Galactic Nucleus 3C 279. We conducted polarization observations for 3C 279 using the SHARP polarimeter in the…
We are using "broadband" (4.6 to 43 GHz) multi-frequency VLBA polarization observations of compact AGN to investigate the 3-D structure of their jet magnetic (B) fields. Observing at several frequencies, separated by short and long…
Preliminary VLBA polarisation results on 6 ``blazars'' from 6.5-cm to 7-mm are presented here. Observing at several different wavelengths, separated by short and long intervals, enabled reliable information about the magnetic (B) field…
We review recent observations of circularly polarized radiation from AGN made with the VLBA and with the ATCA. We also discuss briefly the detections of the Galactic sources Sag A* and SS433. The origin of the circular polarization is still…
We present an analysis of the core linear polarization properties of 387 parsec-scale active galactic nuclei (AGN) jets. Using 15 GHz VLBA data, we revisit the conclusions of the first paper in this series with multi-epoch measurements and…
We report on multi-frequency linear polarization monitoring of 15 active galactic nuclei containing highly relativistic jets with apparent speeds from $\sim$4 $c$ to $>40c$. The measurements were obtained at optical, 1 mm, and 3 mm…
Many radio sources like quasars, blazars, radio galaxies, and micro-quasars exhibit circular polarisation (CP) with surprising temporal persistent handedness. As a possible explanation we propose that the CP is due to Faraday conversion…
With unprecedented angular resolution, the Event Horizon Telescope (EHT) has opened a new era of black holes. We have previously calculated the expected polarization images of M87* with the EHT observations in mind. There, we demonstrated…