Zobrazeno 1 - 10
of 60
pro vyhledávání: '"Vilppu Piirola"'
Autor:
Chien-Ting J. Chen, Ioannis Liodakis, Riccardo Middei, Dawoon E. Kim, Laura Di Gesu, Alessandro Di Marco, Steven R. Ehlert, Manel Errando, Michela Negro, Svetlana G. Jorstad, Alan P. Marscher, Kinwah Wu, Iván Agudo, Juri Poutanen, Tsunefumi Mizuno, Pouya M. Kouch, Elina Lindfors, George A. Borman, Tatiana S. Grishina, Evgenia N. Kopatskaya, Elena G. Larionova, Daria A. Morozova, Sergey S. Savchenko, Ivan S. Troitsky, Yulia V. Troitskaya, Andrey A. Vasilyev, Alexey V. Zhovtan, Francisco José Aceituno, Giacomo Bonnoli, Víctor Casanova, Juan Escudero, Beatriz Agís-González, César Husillos, Jorge Otero Santos, Alfredo Sota, Vilppu Piirola, Ioannis Myserlis, Emmanouil Angelakis, Alexander Kraus, Mark Gurwell, Garrett Keating, Ramprasad Rao, Sincheol Kang, Sang-Sung Lee, Sang-Hyun Kim, Whee Yeon Cheong, Hyeon-Woo Jeong, Chanwoo Song, Andrei V. Berdyugin, Masato Kagitani, Vadim Kravtsov, Anagha P. Nitindala, Takeshi Sakanoi, Ryo Imazawa, Mahito Sasada, Yasushi Fukazawa, Koji S. Kawabata, Makoto Uemura, Tatsuya Nakaoka, Hiroshi Akitaya, Carolina Casadio, Albrecht Sievers, 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, Stefano Ciprini, Enrico Costa, Alessandra De Rosa, Ettore Del Monte, Niccoló Di Lalla, 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, 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, Fabio Muleri, C.-Y. Ng, Stephen L. O’Dell, Nicola Omodei, Chiara Oppedisano, Alessandro Papitto, George G. Pavlov, Abel Lawrence Peirson, Matteo Perri, Melissa Pesce-Rollins, Pierre-Olivier Petrucci, Maura Pilia, Andrea Possenti, Simonetta Puccetti, 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, Fei Xie, Silvia Zane
Publikováno v:
The Astrophysical Journal, Vol 974, Iss 1, p 50 (2024)
We present multiwavelength polarization measurements of the luminous blazar Mrk 501 over a 14 month period. The 2–8 keV X-ray polarization was measured with the Imaging X-ray Polarimetry Explorer (IXPE) with six 100 ks observations spanning from 20
Externí odkaz:
https://doaj.org/article/2d8f1323c5cf4801b599280017133bef
Autor:
Juan Escudero Pedrosa, Iván Agudo, Daniel Morcuende, Jorge Otero-Santos, Giacomo Bonnoli, Vilppu Piirola, César Husillos, Mabel Bernardos, Rubén López-Coto, Alfredo Sota, Victor Casanova, Fran J. Aceituno, Pablo Santos-Sanz
Publikováno v:
The Astronomical Journal, Vol 168, Iss 2, p 84 (2024)
IOP4 is a pipeline to perform photometry and polarimetry analysis of optical data from Calar Alto (CAHA) and Sierra Nevada (OSN) observatories. IOP4 implements Object Relational Mapping to seamlessly integrate all information about the reduction and
Externí odkaz:
https://doaj.org/article/b85e98de862c4e389c8fa469ba803881
Autor:
Lankeswar Dey, Achamveedu Gopakumar, Mauri Valtonen, Stanislaw Zola, Abhimanyu Susobhanan, Rene Hudec, Pauli Pihajoki, Tapio Pursimo, Andrei Berdyugin, Vilppu Piirola, Stefano Ciprini, Kari Nilsson, Helen Jermak, Mark Kidger, Stefanie Komossa
Publikováno v:
Universe, Vol 5, Iss 5, p 108 (2019)
The bright blazar OJ 287 is the best-known candidate for hosting a nanohertz gravitational wave (GW) emitting supermassive binary black hole (SMBBH) in the present observable universe. The binary black hole (BBH) central engine model, proposed by Leh
Externí odkaz:
https://doaj.org/article/cf3b78a65f76450f94cb44835dffc74d
Autor:
Mauri Valtonen, Stanislaw Zola, Helen Jermak, Stefano Ciprini, Rene Hudec, Lankeswar Dey, Achamveedu Gopakumar, Daniel L. Reichart, Daniel B. Caton, Kosmas Gazeas, Katsura Matsumoto, Waldemar Ogloza, Marek Drozdz, Fahri Alicavus, Oleksandr Baransky, Andrei Berdyugin, Panos Boumis, Yurii Bufan, Bartlomiej Debski, Huseyin Er, Ahmet Erdem, Vira Godunova, Shirin Haque, Vivian L. Hoette, Jan Janik, Mark Kidger, Tomasz Kundera, Sebastian Kurowski, Alexis Liakos, Isa Mohammed, Kari Nilsson, Urszula Pajdosz, Vilppu Piirola, Tapio Pursimo, Brandon Rajkumar, Andrii O. Simon, Michal Siwak, Eda Sonbas, Ian A. Steele, Volodymir V. Vasylenko, Michal Zejmo, Pawel Zielinski
Publikováno v:
Galaxies, Vol 5, Iss 4, p 83 (2017)
We report optical photometric and polarimetric observations of the blazar OJ 287 gathered during 2016/17. The high level of activity, noticed after the General Relativity Centenary flare, is argued to be part of the follow-up flares that exhibited hi
Externí odkaz:
https://doaj.org/article/f62e823262d04e028ac9e84bfa1052d2
Autor:
Kunal Deshmukh, Thomas Kupfer, Pasi Hakala, Evan B Bauer, Andrei Berdyugin, Lars Bildsten, Thomas R Marsh, Sandro Mereghetti, Vilppu Piirola
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 519:148-156
We report the results from follow-up observations of two Roche-lobe filling hot subdwarf binaries with white dwarf companions predicted to have accretion disks. ZTF J213056.71+442046.5 (ZTF J2130) with a 39-minute period and ZTF J205515.98+465106.5 (
Aims. The fact that the O-type close binary star system AO Cassiopeiae exhibits variable phase-locked linear polarization has been known since the mid-1970s. In this work, we re-observe the polarization arising from this system more than 50 yr later
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::17940401426378b0b7580e0d93aa6e73
http://arxiv.org/abs/2301.09750
http://arxiv.org/abs/2301.09750
Autor:
Vadim Kravtsov, Andrei V Berdyugin, Ilia A Kosenkov, Alexandra Veledina, Vilppu Piirola, Yasir Abdul Qadir, Svetlana V Berdyugina, Takeshi Sakanoi, Masato Kagitani, Juri Poutanen
Polarimetry provides an avenue for probing the geometry and physical mechanisms producing optical radiation in many astrophysical objects, including stellar binary systems. We present the results of multiwavelength (BVR) polarimetric studies of a sam
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::59153f478def98024c78912017fa52be
http://arxiv.org/abs/2205.12121
http://arxiv.org/abs/2205.12121
Autor:
Juri Poutanen, Ilia A. Kosenkov, Masato Kagitani, Svetlana V. Berdyugina, Takeshi Sakanoi, Vadim Kravtsov, Andrei Berdyugin, Alexandra Veledina, Vilppu Piirola
Publikováno v:
Monthly Notices of the Royal Astronomical Society: Letters. 496:L96-L100
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 optical flu
Autor:
Juri Poutanen, Alexandra Veledina, Andrei V. Berdyugin, Svetlana V. Berdyugina, Helen Jermak, Peter G. Jonker, Jari J. E. Kajava, Ilia A. Kosenkov, Vadim Kravtsov, Vilppu Piirola, Manisha Shrestha, Manuel A. Perez Torres, Sergey S. Tsygankov
Publikováno v:
Science, 375, 874-876
Science, 375, 6583, pp. 874-876
Science, 375, 6583, pp. 874-876
The observational signatures of black holes in x-ray binary systems depend on their masses, spins, accretion rate and the misalignment angle between the black hole spin and the orbital angular momentum. We present optical polarimetric observations of
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0ee5e3fc5e7f765e3f6b29c62c309456
http://hdl.handle.net/2066/247345
http://hdl.handle.net/2066/247345
Autor:
Andrei V. Berdyugin, Vilppu Piirola, Stefano Bagnulo, John D. Landstreet, Svetlana V. Berdyugina
Publikováno v:
Astronomy & Astrophysics. 670:A2
About half of white dwarfs (WDs) evolve to the DC state as they cool; the others become DQ or (temporarily?) DZ WDs. The recent magnetic survey of the local 20 pc volume has established a high frequency of magnetic fields among WDs older than 2-3 Gyr