Results 51 to 60 of about 272 (130)
The Astrophysical JournalWe present here the first systematic search of short-timescale γ -ray flares from 29 high Galactic latitude BL Lac objects over 14 yr of Fermi Large Area Telescope data. Using a combined Bayesian Blocks and HOP algorithm, we identified seven high-quality
Jinjie Yu +4 more
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Rapid Optical Flares in the Blazar OJ 287 on Intraday Timescales with TESS
The Astrophysical Journal, 2023 We have analyzed the optical light curves of the blazar OJ 287 obtained with the Transiting Exoplanet Survey Satellite over about 80 days from 2021 October 13 to December 31, with an unprecedented sampling of 2 minutes.
Shubham Kishore +2 more
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Long-term Optical Spectroscopic Variability of BL Lacertae Object AO 0235+164
The Astrophysical JournalThe changing-look (CL) phenomenon in active galactic nuclei (AGNs) poses a significant challenge to the unified model. As a special subclass of AGN, blazars provide valuable insights.
W. T. He +3 more
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Flux and Spectral Variability of High-Energy-Peaked BL Lacertae Objects in the 0.3–10 keV Band
GalaxiesBL Lacertae objects (BL Lacs) are active galactic nuclei notable for beamed emission generated in the relativistic jets, forming a small angle with respect to our line-of-sight.
Bidzina Kapanadze
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Radio Detection of 18 RASS BL Lac Objects [PDF]
Serbian Astronomical Journal, 2009 We present the radio detection of 18 BL Lac objects from oursurvey of over 575 deg$^2$ of sky. These 18 objects are located within$20arcsec$ of the X-ray position, of which 11 have a measuredred-shift.
Anderson M. W. B., Filipović, M. D.
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BL Lacertae objects and the extragalactic γ-ray background [PDF]
Research in Astronomy and Astrophysics, 2011 12 pages, 4 figures ...
Li, Fan, Cao, Xinwu
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Highly Polarized Optically Selected BL Lacertae Objects [PDF]
The Astrophysical Journal, 2007 9 pages, 3 figures, 2 ...
Smith, Paul S. +4 more
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Classification of Fermi BCUs Using Machine Learning
The Astrophysical Journal, 2023 The Fermi Large Area Telescope (LAT) has detected 6659 γ -ray sources in the incremental version (4FGL-DR3, for Data Release 3) of the fourth Fermi-LAT catalog of γ -ray sources and 3743 of them are blazars, including 1517 blazar candidates of uncertain ...
Pei-yu Xiao +12 more
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ROSAT Observations of BL Lacertae Objects
, 1996 We present soft X-ray spectra of 74 BL Lacertae objects observed with the PSPC detector on board of the ROSAT satellite. The sample contains all BL Lac objects detected during the pointed observation phase as a target or serendipitously. We have investigated the soft X-ray and broad band spectral properties and discuss the consequences for the X-ray ...
Lamer, G., Brunner, H., Staubert, R.
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Multi-Band Optical Variability of Blazar 1ES 2344+514 on Diverse Time-Scales
Journal of Advanced Research in Natural and Applied SciencesThis study presents the results of multi-band observations from 2022 to 2024 and Zwicky Transient Facility (ZTF) observations from 2018 to 2023, examining the flux variability of the blazar 1ES 2344+514 on diverse time-scales in the optical bands.
Aykut Özdönmez
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