Results 71 to 80 of about 1,386,746 (158)

The Study of Radio Flux Density Variations of the Quasar OJ 287 by the Wavelet and the Singular Spectrum Methods

Open Astronomy, 2016
Flux density variations of the extragalactic radio source OJ 287 are studied by applying the wavelet and the singular spectrum methods to the long-term monitoring data at 14.5, 8.0 and 4.8 GHz acquired at the University of Michigan Radio Astronomy ...
Donskykh Ganna
doaj   +1 more source

Soft X-ray properties of a complete sample of radio-selected BL lacertae objects

, 1996
We report the soft X-ray properties of the complete 1 Jy sample of 34 radio-selected B L Lacertae objects (RBLs) as measured with the ROSAT Position Sensitive Proportional Counter.
Sambruna, Rita M., Kollgaard, R. I., Feigelson, Eric D., Perlman, Eric S., Urry, C. Megan, Stocke, John T., Worrall, D. M.   +6 more
core   +1 more source

Multiband Optical Photometric Variability of the Blazar OJ 287 from 2015 to 2025

The Astrophysical Journal Supplement Series
We present the most densely sampled multiband optical photometric observations of the peculiar BL Lacertae object OJ 287 from 2015 to 2025 with a focus on its optical activity on diverse timescales.
Alok C. Gupta, Karan Dogra, Mark Kidger, Mauri J. Valtonen, Paul J. Wiita, Pankaj Kushwaha, Sergey S. Savchenko, Sofia O. Kurtanidze, Svetlana G. Jorstad, Alan P. Marscher, Katsura Matsumoto, Lang Cui, Shao Ming Hu, Goran Damljanovic, Rumen Bachev, O. Vince, Mai Liao, Zhongxiang Wang, A. Darriba, S. Haque, F. S. Alfaro, J. B. Amatller, J. M. F. Andujar, S. Arnold, T. Arranz, M. Bachini, C. L. Barcelo, S. Boeva, G. A. Borman, D. Boyd, D. Buczinski, J. D. Casal, X. Chen, J. M. Cores, F. C. Cucarella, P. U. Devanand, V. Dhiman, L. T. Espasa, J. H. Fan, R. G. Farfan, J. R. Fernandez, F. Garcia, R. C. García, H. Gaur, J. C. Gomez, J. L. S. Gonzalez, J. L. Gonzalez-Carballo, T. S. Grishina, F. H. Grondona, M. F. Gu, H. Guo, V. A. Hagen-Thorn, G. Hurst, S. Ibryamov, R. Z. Ivanidze, N. James, B. Jardine, S. Johnstone, M. D. Jovanovic, N. Kalita, S. Karge, S. Kishore, E. N. Kopatskaya, O. M. Kurtanidze, A. Kurtenkov, E. G. Larionova, E. R. Lorenz, J. Lozano, E. F. Mananes, F. L. Martínez, M. Mobberley, M. Morales-Aimar, D. A. Morozova, M. G. Nikolashvili, Y. Nikolov, R. N. Nogues, P. A. Novikova, L. M. Penas, A. E. Perez, C. Perello, R. Pickard, F. G. Pinilla, G. Poyner, F. Rahmatullaeva, B. Rajkumar, N. G. Ribes, E. Semkov, E. V. Shishkina, M. Stojanovic, A. Strigachev, T. Tripathi, Yu. V. Troitskaya, I. S. Troitskiy, J. Valero, A. A. Vasilyev, B. Villarroel, A. E. Volvach, L. N. Volvach, S. J. Wagner, Z. R. Weaver, Wen-Xin Yang, Z. Zhang, A. V. Zhovtan, W. Zuo, N. Kojiguchi, Y. Sugiura   +105 more
doaj   +1 more source

Evidence for anisotropic motion of the clouds in broad-line regions of BL Lacertae objects

, 2004
The masses of central massive black holes in BL Lac objects are estimated from their host galaxy absolute magnitude M-R at R-band by using the empirical relation between M-R and black hole mass M-bh.
Cao, XW
core  

Discerning Misclassified Flat-spectrum Radio Quasars from Low-frequency-peaked BL Lacertae Objects

The Astrophysical Journal Supplement Series
A sample of 312 low-frequency-peaked BL Lacertae objects (LBLs) and 694 flat-spectrum radio quasars (FSRQs) with the parameters of both redshift and gamma-ray photon spectral index (Γ _γ ) is compiled from the Fourth Catalog of Active Galactic Nuclei ...
S. Liang, W. G. Yang, Y. G. Zheng, S. J. Kang   +3 more
doaj   +1 more source

Multiwavelength Study of Extreme High-energy Peaked BL Lac Source 1ES 0229+200 Using Ultraviolet, X-Ray, and γ-Ray Observations

The Astrophysical Journal
We present a comprehensive analysis of the broadband spectral energy distribution (SED) of the extreme high-energy peaked BL Lac source, 1ES 0229+200. Our study utilizes near-simultaneous data collected at various epochs between 2017 September and 2021 ...
Jyotishree Hota, Rukaiya Khatoon, Ranjeev Misra, Ananta C. Pradhan   +3 more
doaj   +1 more source

Assigning Degrees of Stochasticity to Blazar Light Curves in the Radio Band Using Complex Networks. [PDF]

Entropy (Basel), 2022
Acosta-Tripailao B, Max-Moerbeck W, Pastén D, Moya PS.   +3 more
europepmc   +1 more source

The Spectral Variation Behavior of Fermi-LAT Blazars

The Astrophysical Journal
In this study, we analyze the ∼16 yr Fermi-Large Area Telescope data of 160 blazars consisting of 92 flat-spectrum radio quasars (FSRQs), 64 BL Lacertae (BL Lac)–type objects, and 4 blazar-candidates-of-unknown-type objects, and investigate their ...
Junhao Deng, Yunguo Jiang
doaj   +1 more source

No evidence for radio-quiet BL Lacertae objects

The Astrophysical Journal, 1990
Using a large, flux-limited sample of faint X-ray sources, a search has been conducted for radio-quiet BL Lacertae objects. None has been found. Thirty-two X-ray-selected BL Lac objects and BL Lac candidates have been found within the sources of the Einstein Medium Sensitivity Survey (EMSS).
John T. Stocke, Simon L. Morris, Isabella Gioia, Tommaso Maccacaro, R. E. Schild, A. Wolter   +5 more
openaire   +1 more source

Optical observations of five X-ray selected BL Lacertae objects

, 2000

We present optical data obtained with the 1.05 m telescope of the Torino Astronomical Observatory for five X-ray selected BL Lacertae objects. The data are in the Johnson's B, V, and Cousins' R bands.
C. M. Raiteri, G. De Francesco, L. Lanteri, G. Sobrito, M. Villata, M. D. Popescu, L. Ostorero   +6 more
core   +1 more source