Results 121 to 130 of about 796,792 (175)

A statistical investigation of radio-loudness in SDSS DR16Q quasars using ML-based classification and physical feature analysis

European Physical Journal C: Particles and Fields
The problem of quasar classification comes in the class of highly imbalanced classification problems since Radio-loud quasars are rare and make up very small portion of total quasar population. In this work,We perform classification of Radio-Loud quasars
Ramkrishna Joshi, Vivek Shinde
doaj   +1 more source

New molecular species at redshift <i>z</i> = 0.89. [PDF]

Astron Astrophys, 2020
Tercero B, Cernicharo J, Cuadrado S, de Vicente P, Guélin M.   +4 more
europepmc   +1 more source

NuSTAR Observations of a Varying-flux Quasar in the Epoch of Reionization

The Astrophysical Journal Letters
With enough X-ray flux to be detected in a 160 s scan by SRG/eROSITA, the z = 6.19 quasar CFHQS J142952+544717 is, by far, the most luminous X-ray source known at z  > 6.
Lea Marcotulli, Thomas Connor, Eduardo Bañados, Peter G. Boorman, Giulia Migliori, Brian W. Grefenstette, Emmanuel Momjian, Aneta Siemiginowska, Daniel Stern, Silvia Belladitta, C. C. Cheung, Andrew Fabian, Yana Khusanova, Chiara Mazzucchelli, Sofía Rojas-Ruiz, C. Megan Urry   +15 more
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Multiwavelength analysis of the variability of the blazar 3C 273. [PDF]

Mon Not R Astron Soc, 2020
Fernandes S, Patiño-Álvarez VM, Chavushyan V, Schlegel EM, Valdés JR.   +4 more
europepmc   +1 more source

New Constraints on the Black Hole Spin In Radio Loud Quasars

, 2017
A study comparing the mean radiative efficiencies of carefully matched samples of radio-loud and radio-quiet SDSS quasars at 0 ...
Lu, Youjun, Schulze, Andreas (5114624), Zhang, Fupeng, Done, Chris, Lu, Youjun (5297332), Inoue, Yoshiyuki, Zhang, Fupeng (5297329), Schulze, Andreas, Inoue, Yoshiyuki (5297326), Done, Chris (5114618)   +9 more
core   +1 more source

J-HERTz: J-PLUS Heritage Exploration of Radio Targets at z < 5

The Astrophysical Journal Supplement Series
We introduce J-HERTz (J-PLUS Heritage Exploration of Radio Targets at z < 5), a new multiwavelength catalog that combines optical narrowband photometry from J-PLUS, infrared observations from the Wide-field Infrared Survey Explorer, and deep low ...
D. Fernández Gil, J. A. Fernández-Ontiveros, C. López-Sanjuan, F. Arizo-Borillo, A. del Pino, A. Hernán-Caballero, A. Lumbreras-Calle, P. T. Rahna, David Sobral, H. Vázquez Ramió, A. J. Cenarro, A. Marín-Franch, R. E. Angulo, A. Ederoclite, D. Cristóbal-Hornillos, R. A. Dupke, C. Hernández-Monteagudo, M. Moles, L. Sodré Jr., J. Varela   +19 more
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J1406+0102: A Dust-obscured Galaxy Hiding a Super-Eddington Accretion System with Bright Radio Emission

The Astrophysical Journal
Recent high- z quasar observations strongly indicate that super-Eddington accretion is a crucial phase to describe the presence of supermassive black holes (SMBHs) with M _BH  ≳ 10 ^9 M _⊙ at z  ≳ 7.
Hikaru Fukuchi, Kohei Ichikawa, Masayuki Akiyama, Shigeo S. Kimura, Yoshiki Toba, Kohei Inayoshi, Akatoki Noboriguchi, Toshihiro Kawaguchi, Xiaoyang Chen, Itsna K. Fitriana   +9 more
doaj   +1 more source

Observations of Low and Intermediate Spectral Peak Blazars with the Imaging X-Ray Polarimetry Explorer

The Astrophysical Journal
We present X-ray polarimetry observations from the Imaging X-ray Polarimetry Explorer (IXPE) of three low spectral peak and one intermediate spectral peak blazars, namely 3C 273, 3C 279, 3C 454.3, and S5 0716+714.
Herman L. Marshall, Ioannis Liodakis, Alan P. Marscher, Niccolò Di Lalla, Svetlana G. Jorstad, Dawoon E. Kim, Riccardo Middei, Michela Negro, Nicola Omodei, Abel L. Peirson, Matteo Perri, Simonetta Puccetti, Marco Laurenti, Iván Agudo, Giacomo Bonnoli, Andrei V. Berdyugin, Elisabetta Cavazzuti, Nicole Rodriguez Cavero, Immacolata Donnarumma, Laura Di Gesu, Jenni Jormanainen, Henric Krawczynski, Elina Lindfors, Greg Madjeski, Frédéric Marin, Francesco Massaro, Luigi Pacciani, Juri Poutanen, Fabrizio Tavecchio, Pouya M. Kouch, Francisco José Aceituno, Maria I. Bernardos, Víctor Casanova, Maya García-Comas, Beatriz Agís-González, César Husillos, Alessandro Marchini, Alfredo Sota, Dmitry Blinov, Ioakeim G. Bourbah, Sebastian Kielhmann, Evangelos Kontopodis, Nikos Mandarakas, Stylianos Romanopoulos, Raphael Skalidis, Anna Vervelaki, George A. Borman, Evgenia N. Kopatskaya, Elena G. Larionova, Daria A. Morozova, Sergey S. Savchenko, Andrey A. Vasilyev, Alexey V. Zhovtan, Carolina Casadio, Juan Escudero, Joana Kramer, Ioannis Myserlis, Efthalia Trainou, Ryo Imazawa, Mahito Sasada, Yasushi Fukazawa, Koji S. Kawabata, Makoto Uemura, Tsunefumi Mizuno, Tatsuya Nakaoka, Hiroshi Akitaya, Joseph R. Masiero, Dimitri Mawet, Georgia V. Panopoulou, Samaporn Tinyanont, Masato Kagitani, Vadim Kravtsov, Takeshi Sakanoi, Matthew Dattolo, Mark Gurwell, Garrett Keating, Ramprasad Rao, Whee Yeon Cheong, Hyeon-Woo Jeong, Sincheol Kang, Sang-Hyun Kim, Sang-Sung Lee, Emmanouil Angelakis, Alexander Kraus, Antonio Hales, Seiji Kameno, Ruediger Kneissl, Hugo Messias, Hiroshi Nagai, 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, Chen-Ting Chen, Stefano Ciprini, Enrico Costa, Alessandra De Rosa, Ettore Del Monte, Alessandro Di Marco, Victor Doroshenko, Michal Dovčiak, Steven R. Ehlert, 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, Fabio La Monaca, Luca Latronico, Simone Maldera, Alberto Manfreda, Andrea Marinucci, Giorgio Matt, Ikuyuki Mitsuishi, Fabio Muleri, C.-Y. Ng, Stephen L. O’Dell, Chiara Oppedisano, Alessandro Papitto, George G. Pavlov, Melissa Pesce-Rollins, Pierre-Olivier Petrucci, Maura Pilia, Andrea Possenti, Brian D. Ramsey, John Rankin, Ajay Ratheesh, Oliver J. Roberts, Roger W. Romani, Carmelo Sgrò, 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   +164 more
doaj   +1 more source

Extragalactic radio surveys in the pre-Square Kilometre Array era. [PDF]

R Soc Open Sci, 2017
Simpson C.
europepmc   +1 more source

Compact radio-loud broad absorption line quasars [PDF]

, 2008
For a long time, radio-loud Broad Absorption Line Quasars (BAL QSOs) were thought to be extremely rare objects. The absorbing troughs seen in their optical spectra are due to strong winds which probably have their origin within the inner region of the ...
Carballo Fidalgo, Ruth, Holt, Joanna, González Serrano, José Ignacio, Montenegro-Montes, Francisco M., Mack, Karl-Heinz, Vigotti, Mario, Benn, Chris R., Jiménez Luján, Florencia   +7 more
core   +1 more source