Related papers: A Radio Survey for Linear and Circular Polarizatio…
We report the detection of circular polarization in the compact radio jet of the nearby spiral galaxy M81 (M81*). The observations were made with the Very Large Array at 4.8 and 8.4 GHz and circular polarization was detected at both…
We describe recent results for Sgr A*, M81* and other low luminosity active galactic nuclei. We have conducted linear and circular polarimetry over a frequency range of 1.4 to 230 GHz and detected a variety of phenomena. The polarization…
We present results from archival Very Large Array (VLA) data and new VLA observations to investigate the long term behavior of the circular polarization of M81*, the nuclear radio source in the nearby galaxy M81. We also used the…
We present the results from the first large (>100 source) 3.5 mm polarimetric survey of radio loud active galactic nuclei (AGN). The I, Q, U, and V Stokes parameter observations were performed with the XPOL polarimeter at the IRAM 30m…
Millimeter wavelength polarimetry of accreting black hole systems can provide a tomographic probe of the accretion flow on a wide range of linear scales. We searched for linear polarization in two low luminosity active galactic nuclei…
We report here the detection of circular polarization in the Galactic Center black hole candidate, Sagittarius A*. The detection was made at 4.8 GHz and 8.4 GHz with the Very Large Array. We find that the fractional circular polarization at…
Short millimeter observations of radio-loud AGN offer the opportunity to study the physics of their inner relativistic jets, from where the bulk millimeter emission is radiated. Millimeter jets are significantly less affected by Faraday…
Synchrotron radiation from active galactic nuclei (AGN) is often highly polarized. We present a search for linear polarization with the Very Large Array (VLA) at 4.8 GHz and 8.4 GHz from the nearest AGN, Sagittarius A*. As a part of this…
We have studied the linear polarization of 86 active galactic nuclei (AGN) in the observed frequency range 80-267 GHz (3.7-1.1mm in wavelength), corresponding to rest-frame frequencies 82-738 GHz, with the IRAM Plateau de Bure…
We report a search for linear polarization in the active galactic nucleus (AGN) 3C 84 (NGC 1275) at observed frequencies of 239 GHz and 348 GHz, corresponding to rest-frame frequencies of 243 GHz and 354 GHz. We collected polarization data…
The nearby low-luminosity active galactic nucleus (LLAGN) NGC 4258 has a weak radio continuum emission at the galactic center. Quasi-simultaneous multi-frequency observations using the Very Large Array (VLA) from 5 GHz (6 cm) to 22 GHz (1.3…
Low-luminosity active galactic nuclei (LLAGN; $L_{\rm bol} < 10^{42}$~erg~s$^{-1}$) may comprise a significant fraction of the local AGN population, yet their weak emission makes them difficult to detect. In this paper, we analyse 38 LLAGN…
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 discuss the constraints that recent observations place on circular polarization in AGN. In many sources the circular polarization is variable on short timescales, indicating that it originates in compact regions of the sources. The best…
Radio polarimetry is an invaluable tool to investigate the physical conditions and variability processes in active galactic nuclei (AGN) jets. However, detecting their linear and circular polarization properties is a challenging endeavor…
We present full polarization Very Long Baseline Array (VLBA) observations at 5 GHz and 15 GHz of 24 compact active galactic nuclei (AGN). These sources were observed as part of a pilot project to demonstrate the feasibility of conducting a…
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…
The low-frequency polarisation properties of radio sources are poorly studied, particularly in statistical samples. However, the new generation of low-frequency telescopes, such as the Murchison Widefield Array (MWA; the precursor for the…
The nearby spiral galaxy M81 harbors in its core a Low-Luminosity AGN (LLAGN), and appears closely related to the more distant and powerful AGNs seen in quasars and radio galaxies. The intrinsic size of this object is unknown due to…
In order to determine whether unified models of active galactic nuclei apply to low-luminosity objects, we have undertaken a spectropolarimetric survey of of LINERs and Seyfert nuclei at the Keck Observatory. The 14 objects observed have a…