Results 101 to 110 of about 1,170,090 (200)

The Whole Earth Blazar telescope on BL Lacertae (Poster)

, 2003
The Whole Earth Blazar Telescope (WEBT) is an international consortium of about 30 optical observatories and 2 radio observatories devoted to blazar monitoring during optical and multifrequency campaigns.
N. Okada, J. C. Noble, G. Sobrito, T. Kato, G. Nucciarelli, I. E. Papadakis, C. Pullen, M. T. Carini, R. Ishioka, D. Dultzin Hacyan, J. Basler, A. C. Sadun, L. O. Takalo, K. Sadakane, J. R. Mattox, C. M. Raiteri, V. A. Hagen Thorn, M. Lainela, E. G. Larionova, M. Uemura, H. Karttunen, P. Keinínen, S. Catalano, V. M. Larionov, M. Maesano, J. Papamastorakis, R. M. Robb, E. Benítez, L. Lanteri, J. A. de, A. Oksanen, H. Iwamatsu, R. Nesci, TOSTI, Gino, M. Villata, J. H. Fan, K. Matsumoto, S. G. Jorstad, M. Moilanen, O. M. Kurtanidze, M. Kelly, A. Frasca, A. Sillanpää, R. D. Schwartz, N. A. Kudryavtseva, P. W. Gorham, H. R. Miller, S. Ciprini, M. Pasanen, E. Marilli, F. Montagni, M. G. Nikolashvili, M. A. Ibrahimov, K. Tsinganos, D. Rodriguez, L. Ostorero   +55 more
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Optical and radio variability in blazars

The Astrophysical Journal, 1992
An analysis is presented of the optical (0.44 micron) and radio flux density variations (4.8, 8.0, and 14.5 GHz) of the five best observed variable AGN, of which three are BL Lac objects and two are optically violent variable (OVV) quasars. For each object the nature of the variability at individual wavelengths is determined by using a structure ...
Beth R. Hufnagel, Joel N. Bregman
openaire   +1 more source

Photometric and Polarimetric Interpretation of Blazar AO 0235+164 Behaviour

Atoms, 2017
Among the great number of controversial issues, the most topical one both for theoretical and observational astrophysics presently is a problem of active galactic nuclei investigation.
Elena Shablovinskaya
doaj   +1 more source

X-Ray Intraday Variability of the Blazar OJ 287 Observed with XMM-Newton

The Astrophysical Journal
We present X-ray intraday variability, cross-correlated variability, and power spectrum density analysis of the binary black hole blazar candidate OJ 287.
Tao Huang, Alok C. Gupta, Lang Cui, Ashutosh Tripathi, Yongfeng Huang, P. U. Devanand, Xiang Liu   +6 more
doaj   +1 more source

A Two-week IXPE Monitoring Campaign on Mrk 421

The Astrophysical Journal
X-ray polarization is a unique new probe of the particle acceleration in astrophysical jets made possible through the Imaging X-ray Polarimetry Explorer. Here we report on the first dense X-ray polarization monitoring campaign on the blazar Mrk 421.
W. Peter Maksym, Ioannis Liodakis, M. Lynne Saade, Dawoon E. Kim, Riccardo Middei, Laura Di Gesu, Sebastian Kiehlmann, Gabriele Matzeu, Iván Agudo, Alan P. Marscher, Steven R. Ehlert, Svetlana G. Jorstad, Philip Kaaret, Herman L. Marshall, Luigi Pacciani, Matteo Perri, Simonetta Puccetti, Pouya M. Kouch, Elina Lindfors, Francisco José Aceituno, Giacomo Bonnoli, Víctor Casanova, Juan Escudero, José L. Gómez, Beatriz Agís-González, César Husillos, Daniel Morcuende, Jorge Otero-Santos, Alfredo Sota, Vilppu Piirola, Ryo Imazawa, Mahito Sasada, Yasushi Fukazawa, Koji S. Kawabata, Makoto Uemura, Tsunefumi Mizuno, Tatsuya Nakaoka, Hiroshi Akitaya, Callum McCall, Helen E. Jermak, Iain A. Steele, George A. Borman, Tatiana S. Grishina, Vladimir A. Hagen-Thorn, Evgenia N. Kopatskaya, Elena G. Larionova, Daria A. Morozova, Sergey S. Savchenko, Ekaterina V. Shishkina, Ivan S. Troitskiy, Yulia V. Troitskaya, Andrey A. Vasilyev, Alexey V. Zhovtan, Ioannis Myserlis, Mark Gurwell, Garrett Keating, Ramprasad Rao, Colt Pauley, Emmanouil Angelakis, Alexander Kraus, Andrei V. Berdyugin, Masato Kagitani, Vadim Kravtsov, Juri Poutanen, Takeshi Sakanoi, Sincheol Kang, Sang-Sung Lee, Sang-Hyun Kim, Whee Yeon Cheong, Hyeon-Woo Jeong, Chanwoo Song, Dmitry Blinov, Elena Shablovinskaya, Lucio Angelo Antonelli, Matteo Bachetti, Luca Baldini, Wayne H. Baumgartner, Ronaldo Bellazzini, Stefano Bianchi, Stephen D. Bongiorno, Raffaella Bonino, Alessandro Brez, Niccoló Bucciantini, Fiamma Capitanio, Simone Castellano, Elisabetta Cavazzuti, Chien-Ting Chen, Stefano Ciprini, Enrico Costa, Alessandra De Rosa, Ettore Del Monte, Niccoló 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, Vladimir Karas, Fabian Kislat, Takao Kitaguchi, Jeffery J. Kolodziejczak, Henric Krawczynski, Fabio La Monaca, Luca Latronico, Simone Maldera, Alberto Manfreda, Frédéric Marin, Andrea Marinucci, Francesco Massaro, Giorgio Matt, Ikuyuki Mitsuishi, Fabio Muleri, Michela Negro, C.-Y. Ng, Stephen L. O’Dell, Nicola Omodei, Chiara Oppedisano, Alessandro Papitto, George G. Pavlov, Abel Lawrence Peirson, Melissa Pesce-Rollins, Pierre-Olivier Petrucci, Maura Pilia, Andrea Possenti, Brian D. Ramsey, John Rankin, Ajay Ratheesh, Oliver J. Roberts, Roger W. Romani, Carmelo Sgró, Patrick Slane, Paolo Soffitta, Gloria Spandre, Douglas A. Swartz, Toru Tamagawa, Fabrizio Tavecchio, 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   +156 more
doaj   +1 more source

Blazar spectral variability as explained by a twisted inhomogeneous jet

, 2020
© 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Blazars are active galactic nuclei, which are powerful sources of radiation whose central engine is located in the core of the host galaxy. Blazar emission is dominated by
Echevarría J., Morozova D., Agudo I., Bozhilov V., Gurwell M., Joshi M., Baida G., Marscher A., Michel R., Redondo-Lorenzo F., Efimova N., Butuzova M., Savchenko S., Larionov V., Skiff B., Ehgamberdiev S., Jordan B., Nikolashvili M., Carosati D., Mirzaqulov D., Semkov E., Kurtanidze S., Molina S., Nazarov S., Mihov B., Jermak H., Rizzi N., Hiriart D., Kuratov K., Rodriguez-Coira G., Polakis T., Giunta A., Pursimo T., Acosta-Pulido J., Raiteri C., Grishina T., Larionova L., Casadio C., Okhmat D., Calcidese P., Mokrushina A., Benítez E., Steele I., Matsumoto K., Ovcharov E., Chen W., Lähteenmäki A., Malmrose M., Espinosa C., Villata M., Carnerero M., Arkharov A., McBreen B., Boschin W., Jorstad S., Kurtanidze O., Bachev R., Kopatskaya E., Pinna F., Ohlert J., Castro-Segura N., Damljanovic G., Lázaro C., Borman G., D'Ammando F., Larionova E., Gómez J., Slavcheva-Mihova L., Sadakane K., Lin C., Samal M., Moody J., Smith P., Fuentes A., Protasio C., Di Paola A., Sadun A., Minev M.   +77 more
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Are Multiwavelength Variability Events in Blazars Driven by a Common Stochastic Process?

The Astrophysical Journal
We investigate the underlying stochastic processes driving the multiwavelength variability of the blazar BL Lacertae over the past two decades. Observations from Weihai Observatory over 224 nights reveal that the power spectral slopes of intra-night ...
Jingran Xu, Shaoming Hu, Xu Chen, Shifeng Huang   +3 more
doaj   +1 more source

Comprehensive Analysis of Optical Brightness and Color Variability of Blazars in the ZTF Survey DR22

The Astrophysical Journal
This study conducts a comprehensive analysis of brightness and color variability in blazars, utilizing over 6 yr of quasi-simultaneous g -band and r -band data from 1149 sources in the Zwicky Transient Facility Data Release 22 (DR22), including 589 BL ...
Qi Yuan, Xin Wang, Meng Zhang, Wenwen Zuo, Yan Xu, Chunguo Wu, Ming Zhang, Xiang Liu, Lang Cui   +8 more
doaj   +1 more source

Evidence of Two-Component Optical Polarization in Blazar 1ES 1959+650

EPJ Web of Conferences, 2013
In this work we present an analysis of the optical polarimetric variability of the TeV-blazar 1 ES 1959+650 from 2007 October 18 to 2011 May 5. The source showed a maximum variation of 1.2 mag in R- band, and a maximum polarization degree of 12.2%.
Sorcia Marco, Benítez Erika, Hiriart David   +2 more
doaj   +1 more source

US Climate Variability & Predictability Program Science Plan

, 2013
This report discusses the strategic scientific plan for the United States Climate Variability & Predictability ...
U.S. Climate Variability & Predictability Program. Scientific Steering Committee.
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