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Related papers: Radio Polarization of BL Lacertae objects

200 papers

In this work, we report the presence of rapid intra-night optical variations in both -- flux and polarization of the blazar BL Lacertae during its unprecedented 2020--2021 high state of brightness. The object showed significant flux…

We report on multi-bands VLBA polarimetric observations of NRAO 530 in February 1997. Total intensity, EVPA distributions at all these frequencies are presented. Model fitting has been performed, from which the fitted southmost component A…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Y. J. Chen , Z. -Q. Shen , S. -W. Feng

We investigate quantitatively how the peak emission frequency of the overall energy spectrum is at work in distinguishing RBL-like and XBL-like objects. We employ the sample of Giommi et al. (1995) to study the distribution of BL Lacertae…

Astrophysics · Physics 2009-10-31 Yi-Ping Qin , G. Z. Xie , Xue-Tang Zheng

VLA imaging at kiloparsec-scale resolution of sixteen core-dominated radio-loud QSOs is presented. Many objects appear to display variable radio emission and their radio morphologies are significantly smaller than those of steep-spectrum…

Astrophysics · Physics 2007-05-23 Peter D. Barthel , Marianne Vestergaard , Colin J. Lonsdale

This chapter introduces the concepts of polarimetry in the case of low frequency radio astronomy. In this regime radio waves are usually not the signature of atomic or molecular transitions lines, but rather that of unstable particle…

Instrumentation and Methods for Astrophysics · Physics 2019-01-14 Baptiste Cecconi

(Abriged) Intranight polarization variability in AGN has not been studied extensively so far. Studying the variability in polarization makes it possibly to distinguish between different emission mechanisms. Thus it can help answering the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 C. Villforth , K. Nilsson , R. Ostensen , J. Heidt , S. -M. Niemi , J. Pforr

Blazars are powerful, variable emitters from radio to gamma-ray wavelengths. Even though the general picture of synchrotron emission at low energies and inverse Compton at the high energy end is well established, many important aspects of…

High Energy Astrophysical Phenomena · Physics 2019-08-15 W. Max-Moerbeck , J. L. Richards , V. Pavlidou , T. J. Pearson , A. C. S. Readhead , T. Hovatta , O. G. King , R. Reeves

We report radio imaging and monitoring observations in the frequency range 0.235 - 2.7 GHz during the flaring mode of PKS 2155-304, one of the brightest BL Lac objects. The high sensitivity GMRT observations not only reveal extended…

High Energy Astrophysical Phenomena · Physics 2016-10-19 M. Pandey-Pommier , S. Sirothia , P. Chadwick , J. -M. Martin , P. Colom , W. van Driel , F. Combes , P. Kharb , P-J. Crespeau , J. Richard , B. Guiderdoni

Rotation measure observations of 9 quasars, 4 BL Lacertae objects, and 3 radio galaxies are presented. The rest frame rotation measures in the cores of the quasars and the jets of the radio galaxy M87 are several thousand radians per meter…

Astrophysics · Physics 2008-11-26 R. T. Zavala , G. B. Taylor

We have conducted observations of 22 pulsars at frequencies of 0.7, 1.4 and 3.1 GHz and present their polarization profiles. The observations were carried out for two main purposes. First we compare the orientation of the spin and velocity…

Astrophysics · Physics 2009-11-13 Simon Johnston , M. Kramer , A. Karastergiou , G. Hobbs , S. Ord , J. Wallman

We put forward a scenario where blazars are classified as flat-spectrum radio quasars, BL Lacs, low synchrotron, or high synchrotron peaked objects according to a varying combination of Doppler boosted radiation from the jet, emission from…

High Energy Astrophysical Phenomena · Physics 2012-05-04 P. Padovani , P. Giommi , G. Polenta , S. Turriziani , V. D'Elia , S. Piranomonte

A set of potentially gamma-ray--loud BL Lac objects is selected by intersecting the EGRET and BL Lac catalogs. Of the resulting 14 objects, eight are found to correlate with arrival directions of ultra--high-energy cosmic rays (UHECRs),…

Astrophysics · Physics 2009-11-07 D. Gorbunov , P. Tinyakov , I. Tkachev , S. Troitsky

We define a complete sample of thirty-three GHz-Peaked-Spectrum (GPS) radio sources based on their spectral properties. We present measurements of the radio spectra and polarization of the complete sample and a list of additional GPS…

Astrophysics · Physics 2016-08-30 C. Stanghellini , C. P. O'Dea , D. Dallacasa , S. A. Baum , R. Fanti , C. Fanti

In a cycle of papers, starting with the present one, a fundamental possibility of the polarization sounding of a pulsar magnetosphere using pulsar self-radiation as a test signal will be considered. The main idea of such a sounding is based…

Astrophysics of Galaxies · Physics 2014-11-25 O. M. Ulyanov , A. I. Shevtsova , A. O. Skoryk

Emission from blazar jets in the ultraviolet, optical, and infrared is polarized. If these low-energy photons were inverse-Compton scattered, the upscattered high-energy photons retain a fraction of the polarization. Current and future…

High Energy Astrophysical Phenomena · Physics 2015-02-03 Nachiketa Chakraborty , Vasiliki Pavlidou , Brian Fields

We have performed a multi-dimensional correlation analysis on the observed properties of a statistically complete core-selected sample of compact radio-loud active galactic nuclei, based on data from the VLBI Space Observing Programme…

Astrophysics · Physics 2009-11-06 M. L. Lister , S. J. Tingay , R. A. Preston

Polarised radio synchrotron emission from interstellar, intracluster and intergalactic magnetic fields is affected by frequency-dependent Faraday depolarisation. The maximum polarised intensity depends on the physical properties of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Tigran G. Arshakian , Rainer Beck

Fast radio bursts (FRBs) are one of the most tantalizing mysteries of the radio sky; their progenitors and origins remain unknown and until now no rapid multiwavelength follow-up of an FRB has been possible. New instrumentation has…

We present a broadband polarization analysis of 36 discrete polarized radio sources over a very broad, densely-sampled frequency band. Our sample was selected on the basis of polarization behaviour apparent in narrowband archival data at…

High Energy Astrophysical Phenomena · Physics 2016-07-06 C. S. Anderson , B. M. Gaensler , I. J. Feain

We present the results of an extensive analysis of the optical, ultraviolet, X-ray and $\gamma$-ray data collected from the observations of the BL Lac objects prototype BL Lacertae carried out over a period of nearly 13 years, between…

High Energy Astrophysical Phenomena · Physics 2022-04-20 N. Sahakyan , P. Giommi