Discovery of transient high-energyγ-ray emission from the BL Lacertae object 5C 3.178
نویسندگان
چکیده
منابع مشابه
Discovery of very high-energy γ-ray emission from the LBL object BL Lacertae
The low-frequency peaked BL Lac (LBL) object BL Lacertae was observed with the MAGIC telescope from 2005 August to December (22.2 hr), and from 2006 July to September (26.0 hr). A very high energy (VHE) γ-ray signal was discovered with a 5.1 σ excess in the 2005 data. Above 200 GeV, an integral flux of (0.6± 0.2) × 10 cm s was measured, corresponding to approximately 3% of the Crab flux. The di...
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We present results from observations of 29 BL Lacertae objects, taken with the Whipple Observatory 10m Gamma-Ray Telescope between 1995 and 2000. The observed objects are mostly at low redshift (z < 0.2) but observations of objects of z up to 0.444 are also reported. Five of the objects are EGRET sources and two are unconfirmed TeV sources. Three of the confirmed sources of extragalactic TeV ga...
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The bright X-ray–selected BL Lacertae object PKS 21552304 has been the target of two intense multiwavelength campaigns: in 1991 November and in 1994 May. Although the spectral energy distributions at both epochs were quite similar, the source exhibited two very distinct variability patterns that cannot be easily reconciled with homogeneous, one-zone jet models. During the first epoch the variab...
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متن کاملVariability of the BL Lacertae Object PKS 2155 − 304
We present a detailed power density spectrum and cross-correlation analysis of the X-ray light curves of the BL Lac object PKS 2155−304 observed with BeppoSAX in 1997 (SAX97) and 1996 (SAX96), aimed at exploring the rapid variability properties and the inter-band cross correlations in the X-rays. We also perform the same analysis on the (archival) X-ray light curve obtained with ASCA in 1994 (A...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2013
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201321287