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Related papers: Deriving AGN properties from radio CP and LP

200 papers

We have carried out observations at 18.5 GHz with the Australia Telescope Compact Array (ATCA) of 250 out of the 258 Southern extragalactic sources in the complete 5 GHz 1 Jy sample by K\"uhr et al. (1981). In this paper we focus on the…

Astrophysics · Physics 2009-11-10 R. Ricci , I. Prandoni , C. Gruppioni , R. J. Sault , G. De Zotti

We present the largest ever sample of radio polarization properties for $z>4$ sources, with 14 sources having significant polarization detections. Using wideband data from the Karl G. Jansky Very Large Array, we obtained the rest-frame…

Astrophysics of Galaxies · Physics 2018-02-07 Tessa Vernstrom , Bryan Gaensler , Valentina Vacca , Jamie Farnes , Marijke Haverkorn , Shane O'Sullivan

Polarisation measurements of solar flares at millimetre-waves were used to investigate the magnetic field configuration of the emitting sources. We analyse two solar flares (SOL2013-02-17 and SOL2013-11-05) observed by the POlarisation…

Solar and Stellar Astrophysics · Physics 2020-05-05 Douglas F. da Silva , Paulo J. A. Simões , R. F. Hidalgo Ramírez , Adriana Válio

Four Stokes parameters (1852) define the polarisation state of light. Measured changes of the Stokes vector of light traversing an inhomogeneous sample are linked to the local anisotropies of absorption and refraction and are harnessed over…

We have used the Very Large Array aperture synthesis telescope to conduct a radio continuum survey of polar-ring galaxies, at 20cm and 6cm. Forty objects were observed at 20cm with 5" resolution. Twenty (50%) of the program sources were…

Astrophysics · Physics 2009-11-10 A. L. Cox , L. S. Sparke

We present a novel system to calibrate millimeter-wave polarimeters for CMB polarization measurements. This technique is an extension of the conventional metal mirror rotation approach, however it employs cryogenically-cooled blackbody…

Instrumentation and Methods for Astrophysics · Physics 2012-05-01 M. Hasegawa , O. Tajima , Y. Chinone , M. Hazumi , K. Ishidoshiro , M. Nagai

The broad energy range spanned by ASTRO-H instruments, from ~0.3 to 600 keV, with its high spectral resolution calorimeter and sensitive hard X-ray imaging, offers unique opportunities to study black holes and their environments. The…

High Energy Astrophysical Phenomena · Physics 2019-08-14 P. Coppi , L. Stawarz , C. Done , Y. Fukazawa , P. Gandhi , K. Hagino , S. LaMassa , P. Laurent , G. Madejski , T. Mizuno , K. Mukai , H. Odaka , H. Tajima , Y. Tanaka , F. Tombesi , M. Urry

Several on-going and future experiments use a Stokes polarimeter (i.e. a rotating wave plate followed by a steady polarizer and by an unpolarized detector) to measure the small polarized component of the Cosmic Microwave Background. The…

Instrumentation and Methods for Astrophysics · Physics 2010-06-17 Maria Salatino , Paolo de Bernardis

Polarized radio emission of RRAT J1854+0306 is investigated with single pulses using Five-hundred-meter-Aperture Spherical Telescope. Its emission is characterized by nulls, narrow and weak pulses, and occasional wide and intense bursts…

High Energy Astrophysical Phenomena · Physics 2024-04-26 Qi Guo , Minzhi Kong , P. F. Wang , Y. Yan , D. J. Zhou

X-ray polarimetric missions planned for this decade will significantly enhance our knowledge of compact accreting sources. Observations of the X-ray polarization signal from active galactic nuclei (AGNs) or X-ray binary systems (XRBs) will…

High Energy Astrophysical Phenomena · Physics 2023-04-25 Jakub Podgorný , Michal Dovčiak , Frédéric Marin , René Goosmann , Agata Różańska

We demonstrate a mesoscopic spin polarizer/analyzer system that allows the spin polarization of current from a quantum point contact in an in-plane magnetic field to be measured. A transverse focusing geometry is used to couple current from…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 R. M. Potok , J. A. Folk , C. M. Marcus , V. Umansky

One of the main challenges for polarimetric observations of active galactic nuclei (AGN) is to properly estimate the amount of parasitic light that contaminates the polarization signal. Removing this unpolarized flux is a complex task that…

High Energy Astrophysical Phenomena · Physics 2018-08-15 F. Marin

Light's polarisation contains information about its source and interactions, from distant stars to biological samples. Polarimeters can recover this information, but reliance on birefringent or rotating optical elements limits their…

Instrumentation and Detectors · Physics 2018-08-21 Ryan D. Hawley , John Cork , Neal Radwell , Sonja Franke-Arnold

Magnetic fields in cool stars are ubiquitous but can still be challenging to characterize due to their complexity and relatively low strength. The polarization signature amplitudes are proportional to the field strength, and current studies…

Solar and Stellar Astrophysics · Physics 2014-08-19 L. Rosén , O. Kochukhov , G. A. Wade

A radio spectro-polarimeter was developed at the Gauribidanur radio observatory to study the characteristics of the polarized radio waves that are emitted by the impetuous solar corona in the 50 - 500 MHz frequency range. The instrument has…

Instrumentation and Methods for Astrophysics · Physics 2021-01-14 Anshu Kumari , G. V. S. Gireesh , C. Kathiravan , V. Mugundhan , Indrajit V. Barve

We report on the investigation of a complete sample of young radio-loud AGN at z<0.25, selected using the new comprehensive radio surveys and the optical APM/POSS-I catalog. This new sample will provide a unique opportunity for statistical…

Astrophysics · Physics 2007-05-23 I. A. G. Snellen , K. -H. Mack , W. Tschager , R. T. Schilizzi

An approach for measuring linear X-ray polarization over a broad-band using conventional spectroscopic optics is described. A set of multilayer-coated flats reflect the dispersed X-rays to the instrument detectors. The intensity variation…

Astrophysics · Physics 2009-11-13 Herman L. Marshall

Full polarization measurements of 1665 and 1667-MHz OH masers at sites of massive star formation have been made with the Parkes 64-m radio telescope. Here we present the resulting spectra for 104 northerly sources. For more than 20 masers…

Astrophysics of Galaxies · Physics 2014-02-12 J. L. Caswell , J. A. Green , C. J. Phillips

We review the tools and procedures for the analysis of the data collected by X-ray photoelectric gas polarimeters, like the ones on-board the Imaging X-ray Polarimetry Explorer (IXPE). Although many of such tools are in principle common…

Instrumentation and Methods for Astrophysics · Physics 2023-04-05 Fabio Muleri

We present diffraction limited, 10um imaging polarimetry data for the central regions of the archetypal Seyfert AGN, NGC1068. The position angle of polarization is consistent with three dominant polarizing mechanisms. We identify three…