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Related papers: Optical circular polarization of blazar S4 0954+65…

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We present results from our radio polarimetric study with the upgraded Giant Metrewave Radio Telescope (uGMRT) at Band 4 (550-850 MHz) of 3 blazars: radio-loud quasars 3C390.3, 4C71.07 and BL Lac object 1ES 2344+514. The aim of this study…

Astrophysics of Galaxies · Physics 2022-11-30 Janhavi Baghel , Silpa S. , P. Kharb , B. Sebastian , P. Shastri

We describe the first complete polarimetric dataset of the entire outburst of a low-mass black hole X-ray binary system and discuss the constraints for geometry and radiative mechanisms it imposes. During the decaying hard state, when the…

We present an analysis of the cross-correlation between optical brightness and polarization degree in different types of blazars. The aim is to identify objects with simultaneous and consistent changes in characteristics and to determine if…

The spectacular images of the M87 black hole taken by the Event Horizon Telescope (EHT) have opened a new era of black hole research. One of the next issues is to take polarization images around the central black hole (BH). Since radio…

High Energy Astrophysical Phenomena · Physics 2020-03-18 Yuh Tsunetoe , Shin Mineshige , Ken Ohsuga , Tomohisa Kawashima , Kazunori Akiyama

In this work we present the highest spatial and spectral resolution integral field observations to date of the bipolar jet from the Orion proplyd 244-440 using MUSE NFM) observations on the VLT. We observed a previously unreported chain of…

In this work we present a revised measurement of the phase-averaged optical polarisation of the Vela pulsar (PSR B0833-45), for which only one value has been published so far (Wagner & Seifert 2000). Our measurement has been obtained…

Astrophysics · Physics 2009-11-13 R. P. Mignani , S. Bagnulo , J. Dyks , G. Lo Curto , A. Slowikowska

Models of the resolved Event Horizon Telescope (EHT) sources Sgr A* and M87* are constrained by observations at multiple wavelengths, resolutions, polarizations, and time cadences. In this paper we compare unresolved circular polarization…

High Energy Astrophysical Phenomena · Physics 2024-06-25 Abhishek V. Joshi , Ben S. Prather , Chi-kwan Chan , Maciek Wielgus , Charles F. Gammie

We present optical photo-polarimetric observations with high temporal resolution of the blazar AO 0235+164. Our data, the first to test the photo-polarimetric behaviour of this object at very short time-scales, show significant…

Astrophysics · Physics 2009-06-09 Sergio A. Cellone , Gustavo E. Romero , Jorge A. Combi , Josep Marti

Spectropolarimetry is a powerful tool to investigate the central regions of active galactic nuclei (AGNs) as polarization signatures are key to probing magnetic field structure, evolution, and the physics of particle acceleration in jets.…

Astrophysics of Galaxies · Physics 2024-06-26 Stephanie A. Podjed , Ryan C. Hickox , Jedidah C. Isler , Markus Böttcher , Hester M. Schutte

We present the results of a systematic observational campaign designed to search for microvariability in the optical polarization of BL Lac objects. We have observed a sample formed by 8 X-ray-selected and 10 radio-selected sources, looking…

Astrophysics · Physics 2009-11-11 I. Andruchow , G. E. Romero , S. A. Cellone

Multifrequency polarimetry is emerging as a powerful probe of blazar jets, especially due to the advent of the Imaging X-ray Polarimetry Explorer (IXPE) space observatory. We study the polarization of High-Synchrotron Peaked (HSP) blazars,…

High Energy Astrophysical Phenomena · Physics 2024-11-26 F. Bolis , E. Sobacchi , F. Tavecchio

The polarization signatures of the blazar emissions are known to be highly variable. In addition to small fluctuations of the polarization angle around a mean value, sometimes large (> 180^o) polarization angle swings are observed. We…

High Energy Astrophysical Phenomena · Physics 2015-06-24 Haocheng Zhang , Xuhui Chen , Markus Boettcher , Fan Guo , Hui Li

Among active galactic nuclei, blazars show extreme variability properties. We here investigate the case of the BL Lac object S4 0954+65 with data acquired in 2019-2020 by the Transiting Exoplanet Survey Satellite (TESS) and by the Whole…

High Energy Astrophysical Phenomena · Physics 2021-05-12 C. M. Raiteri , M. Villata , V. M. Larionov , S. G. Jorstad , A. P. Marscher , Z. R. Weaver

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…

Astrophysics · Physics 2008-11-26 D. C. Homan , M. L. Lister

Comet NEAT C/2001 Q4 was observed for linear polarization using the optical polarimeter mounted at the 1.2m telescope at Mt. Abu Observatory, during the months of May and June 2004. Observations were conducted through the International…

Earth and Planetary Astrophysics · Physics 2015-05-13 S. Ganesh , U. C. Joshi , K. S. Baliyan

We present polarization images of 9 radio-loud (RL) quasars from the VLA B-array at 6 GHz. These quasars belong to the Palomar-Green (PG) "blazar" sample comprising 16 RL quasars and 8 BL Lac objects. Extensive polarization is detected in…

Astrophysics of Galaxies · Physics 2022-12-28 Janhavi Baghel , P. Kharb , Silpa S. , Luis C. Ho , C. M. Harrison

We suppose that linear optical polarization is due to multiple scattering in optically thick magnetized accretion disk around central black hole. The polarization degree is very sensitive to the spin of black hole - for Kerr rotating hole…

High Energy Astrophysical Phenomena · Physics 2010-11-10 N. A. Silant'ev , M. Yu. Piotrovich , Yu. N. Gnedin , T. M. Natsvlishvili

We present polarization measurements in the $2-8 \thinspace \mathrm{keV}$ band from blazar 1ES 0229+200, the first extreme high synchrotron peaked source to be observed by the Imaging X-ray Polarimetry Explorer (IXPE). Combining two…

High Energy Astrophysical Phenomena · Physics 2023-10-04 Steven R. Ehlert , Ioannis Liodakis , Riccardo Middei , Alan P. Marscher , Fabrizio Tavecchio , Iván Agudo , Pouya M. Kouch , Elina Lindfors , Kari Nilsson , Ioannis Myserlis , Mark Gurwell , Ramprasad Rao , Francisco Jose Aceituno , Giacomo Bonnoli , Victor Casanova , Beatriz Agiz-Gonzalez , Juan Escudero , Jorge Otero Santos , Alfredo Sota , Emmanouil Angelakis , Alexander Kraus , Garrett K. Keating , Lucio A. Antonelli , Matteo Bachetti , Luca Baldini , Wayne H. Baumgartner , Ronaldo Bellazzini , Stefano Bianchi , Stephen D. Bongiorno , Raffaella Bonino , Alessandro Brez , Niccolò Bucciantini , Fiamma Capitanio , Simone Castellano , Elisabetta Cavazzuti , Chien-Ting Chen , Stefano Ciprini , Enrico Costa , Alessandra De Rosa , Ettore Del Monte , Laura Di Gesu , Niccolò Di Lalla , Alessandro Di Marco , Immacolata Donnarumma , Victor Doroshenko , Michal Dovčiak , Teruaki Enoto , Yuri Evangelista , Sergio Fabiani , Riccardo Ferrazzoli , Javier A. Garcia , Shuichi Gunji , Kiyoshi Hayashida , Jeremy Heyl , Wataru Iwakiri , Svetlana G. Jorstad , Philip Kaaret , Vladimir Karas , Fabian Kislat , Takao Kitaguchi , Jeffery J. Kolodziejczak , Henric Krawczynski , Fabio La Monaca , Luca Latronico , Simone Maldera , Alberto Manfreda , Frédéric Marin , Andrea Marinucci , Herman L. Marshall , Francesco Massaro , Giorgio Matt , Ikuyuki Mitsuishi , Tsunefumi Mizuno , Fabio Muleri , Michela Negro , C. -Y. Ng , Stephen L. O'Dell , Nicola Omodei , Chiara Oppedisano , Alessandro Papitto , George G. Pavlov , Abel L. Peirson , Matteo Perri , Melissa Pesce-Rollins , Pierre-Olivier Petrucci , Maura Pilia , Andrea Possenti , Juri Poutanen , Simonetta Puccetti , Brian D. Ramsey , John Rankin , Ajay Ratheesh , Oliver J. Roberts , Roger W. Romani , Carmelo Sgro , Patrick Slane , Paolo Soffitta , Gloria Spandre , Douglas A. Swartz , Toru Tamagawa , Roberto Taverna , Yuzuru Tawara , Allyn F. Tennant , Nicholas E. Thomas , Francesco Tombesi , Alessio Trois , Sergey S. Tsygankov , Roberto Turolla , Jacco Vink , Martin C. Weisskopf , Kinwah Wu , Fei Xie , Silvia Zane

We present the results of an observational photo-polarimetry campaign of the blazar PG 1553+113 at optical wavelengths. The blazar was recently detected at very high energies (> 100 GeV) by the H.E.S.S and MAGIC gamma-ray Cherenkov…

High Energy Astrophysical Phenomena · Physics 2015-05-28 I. Andruchow , J. A. Combi , A. J. Muñoz-Arjonilla , G. E. Romero , S. A. Cellone , J. Martí

In inhomogeneous optically thick synchrotron sources a substantial part of the electron population at low energies can be hidden by self-absorption and overpowered by high energy electrons in optically thin emission. These invisible…

Astrophysics · Physics 2009-11-07 Thomas Beckert , Heino Falcke