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Related papers: Radio Polarization of BL Lacertae objects

200 papers

We report on 16 BL Lacertae objects that were proposed to be at z > 1. We present spectroscopic observations secured at the 10.4m GTC that allowed us to assess the redshift of these sources. In particular, for five objects we disprove the…

High Energy Astrophysical Phenomena · Physics 2018-07-25 M. Landoni , S. Paiano , R. Falomo , R. Scarpa , A. Treves

We present polarization images with the Karl G. Jansky Very Large Array (VLA) in A and B-array configurations at 6 GHz of 7 radio-loud (RL) quasars and 8 BL Lac objects belonging to the Palomar-Green (PG) `blazar' sample. This completes our…

Astrophysics of Galaxies · Physics 2024-11-12 Janhavi Baghel , P. Kharb , T. Hovatta , Luis C. Ho , C. Harrison , E. Lindfors , Silpa S. , S. Gulati

We present total-intensity and linear-polarization observations made with the Very Large Array at $\lambda$20 and 6 cm of a representative sample of 42 radio galaxies and quasars selected from the Molonglo Complete Sample. The sources have…

Astrophysics · Physics 2009-10-31 C. H. Ishwara-Chandra , D. J. Saikia , V. K. Kapahi , P. J. McCarthy

We have collected a large amount of multifrequency data for the objects in the Metsahovi Radio Observatory BL Lacertae sample and computed their spectral energy distributions (SED). This is the first time the SEDs of BL Lacs have been…

Astrophysics · Physics 2008-11-26 E. Nieppola , M. Tornikoski , E. Valtaoja

We present a broadband spectropolarimetric survey of 563 discrete, mostly unresolved radio sources between 1.3 \& 2.0 GHz using data taken with the Australia Telescope Compact Array (ATCA). We have used rotation measure synthesis to…

Astrophysics of Galaxies · Physics 2015-12-16 C. S. Anderson , B. M. Gaensler , I. J. Feain , T. M. O. Franzen

New polarimetric observations of the Crab pulsar at frequencies between 1.4 and 8.4 GHz are presented. Additional pulse components discovered in earlier observations (Moffett & Hankins 1996, astro-ph/9604163) are found to have high levels…

Astrophysics · Physics 2009-10-31 D. A. Moffett , T. H. Hankins

Since late 2007, we have been monitoring a large sample of known and likely gamma-ray-loud blazars at 15 GHz twice per week with the Owens Valley Radio Observatory (OVRO) 40 m Telescope. Our initial sample included the 1158 sources above…

\textbf{Context.} Deep optical surveys open the avenue for find large numbers of BL Lac objects that are hard to identify because they lack the unique properties classifying them as such. While radio or X-ray surveys typically reveal dozens…

Astrophysics of Galaxies · Physics 2014-09-30 S. D. Kügler , K. Nilsson , J. Heidt , J. Esser , T. Schultz

Observations at millimetre wavelengths are presented for a representative sample of 22 X-ray-selected BL Lac objects (XBLs). This sample comprises 19 High-energy cutoff BL Lacs objects (HBLs), 1 Low-energy cutoff BL Lac object (LBL) and 2…

Astrophysics · Physics 2009-10-31 J. A. Stevens , W. K. Gear

A sample of 129 unresolved radio sources with ultrahigh linear polarization (>30 per cent) has been selected from the NRAO VLA Sky Survey. Such high average linear polarization is unusual in extragalactic sources. Higher resolution…

Astrophysics of Galaxies · Physics 2010-09-21 H. Shi , H. Liang , J. L. Han , R. W. Hunstead

We present some first results on the variability, polarization and general properties of radio sources selected in a blind survey at 20 GHz, the highest frequency at which a sensitive radio survey has been carried out over a large area of…

Using the first station of the Long Wavelength Array (LWA1), we examine polarized pulsar emission between 25 and 88 MHz. Polarized light from pulsars undergoes Faraday rotation as it passes through the magnetized interstellar medium.…

High Energy Astrophysical Phenomena · Physics 2020-07-01 V. Dike , G. B. Taylor , J. Dowell , K. Stovall

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…

Astrophysics · Physics 2009-11-11 Andreas Brunthaler , Geoffrey C. Bower , Heino Falcke

We present results of multifrequency polarimetric VLBA observations of 34 compact radio sources. The observations are part of a large survey undertaken to identify CSOs Observed in the Northern Sky (COINS). Based on VLBI continuum surveys…

Astrophysics · Physics 2007-05-23 A. B. Peck , G. B. Taylor

Fast radio bursts (FRBs) are extra-galactic sources with unknown physical mechanisms. They emit millisecond-duration radio pulses with isotropic equivalent energy of $10^{36}\sim10^{41}$ ergs. This corresponds to a brightness temperature of…

We report preliminary results of our study of linear polarization in the pulsar emission at 35 & 327 MHz. We have exploited for this purpose the spectral modulation resulting from the differential Faraday rotation across the observed band.…

Astrophysics · Physics 2007-05-23 Ashish Asgekar , A. A. Deshpande

In this work, we explore the long-term variability properties of the blazar PKS 0219-164 in the radio and the $\gamma$-ray regime, utilizing the OVRO 15 GHz and the \fermi/LAT observations from the period 2008--2017. We found that…

High Energy Astrophysical Phenomena · Physics 2017-09-20 Gopal Bhatta

Low-frequency radio surveys allow in-depth studies and new analyses of classes of sources previously known and characterised only in other bands. In recent years, low radio frequency observations of blazars have been available thanks to new…

Astrophysics of Galaxies · Physics 2020-01-08 Daniele d'Antonio , Marcello Giroletti , Gabriele Giovannini , Alessandro Maini