Spectroscopic monitoring of the BL Lac object AO 0235+164
نویسندگان
چکیده
منابع مشابه
Spectroscopic monitoring of the BL Lac object AO 0235 + 164 ⋆
Aims. Spectroscopic monitoring of BL Lac objects is a difficult task that nonetheless can provide important information on the different components of the active galactic nucleus. Methods. We performed optical spectroscopic monitoring of the BL Lac object AO 0235+164 (z = 0.94) with the VLT and TNG telescopes from Aug. 2003 to Dec. 2004, during an extended WEBT campaign. The flux of this source...
متن کاملVSOP Monitoring of the Compact BL Lac Object AO 0235 + 164 Sándor
In 1999, the highly compact and variable BL Lac object AO 0235+164 was identified as the highest brightness temperature active galactic nucleus observed with the VLBI Space Observatory Programme (VSOP), with TB > 5.8× 1013K (Frey et al. 2000). The sub-milliarcsec radio structure of this source has been studied with dualfrequency (1.6 and 5GHz), polarization-sensitive VSOP observations during 20...
متن کاملHarmonic QPOs and Thick Accretion Disk Oscillations in BL Lac Object AO 0235 + 164
Periodic outbursts are observed in many AGNs and usually explained with a supermassive black hole binary (SMBHB) scenario. However, multiple periods are observed in some AGNs and cannot be explained with it. Here we analyze the periodicity of the radio light curves of AO 0235+164 at multi-frequencies and report the discovery of six QPOs in integer ratio 1:2:3:4:5:6 of QPO frequencies, of which ...
متن کاملISO observations of the BL Lac object PKS 2155 – 304 ⋆
The BL Lacertae object PKS 2155–304 was observed by the Infrared Space Observatory in May and June 1996, during a multiwavelength campaign. These are the first observations in the mid– and far–infrared bands since IRAS. In the observing period, the source showed no detectable time variability at 4.0, 14.3, 60 and 90 μm. The spectrum from 2.8 to 100 μm is well fitted by a single power law with e...
متن کاملEVN Observations of the BL Lac object ON 231 ⋆
New EVN images at 5.0 GHz and 8.4 GHz of ON 231 confirm the complex structure of the source, the identification of the core, the presence of components on the two sides of the core itself and a low brightness extension SouthEast of the main jet. The optical behaviour of the source is discussed in connection to changes in the radio structure.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2007
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20066599