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MOJAVE is a VLBI program which monitors a statistically complete, radio-selected sample of 135 relativistically beamed, flat-spectrum active galactic nuclei for over more than a decade. In order to understand the high-energy behavior of this radio co mplete sample, we are performing Swift fill-in observations on the complete MOJAVE-I sample since 2007. The complete study of the spectral energy distribution from radio to X-ray bands on this radio-selected sample will provide us an opportunity to understand the nature of AGN. Here we present the preliminary results of the spectral energy distributions of six gamma-quiet or faint sources from this project: NRAO 140, PKS 0403-13, PKS B0422+004, PKS 0823+033, 3C 309.1, and 3C 380.
The radio loud galaxy NGC 1052 is being studied in an intensive multi-band campaign including X-ray brigthness monitoring and spectroscopic observations, single-dish radio brightness monitoring at centimetre wavelengths, and a high-frequency very-lon g-baseline interferometry monitoring program. Here we present a progress report on our studies from this program. The final goal of our observations is to relate the findings from the high-resolution radio images with the observed variations in the X-ray regime, to address the accretion processes and their relationship with the radio jet activity.
84 - Eduardo Ros 2008
The radio source M81* at the core of the nearby spiral galaxy M81 is a low-luminosity active galactic nucleus. The close distance of 3.63Mpc allows its morphology to be studied in great detail. Here we present preliminary results from continuum 7 mm VLBI observations of its core, using phase-referencing techniques. These observations set constrains on the size of M81* at this frequency and enable us to test the frequency dependence on its physical properties.
We have studied the inner regions of the LINER galaxy NGC1052 since the mid 1990s at high resolution with 15 GHz very-long-baseline interferometry observations. A compact, two-sided jet structure is revealed, with multiple sub-parsec scale features m oving outward from the central region with typical speeds of 0.26 c. Complementary to this, since early 2005 we are performing a multi-mission campaign of observations of this source, including X-ray spectroscopy, X-ray, and radio flux density monitoring, and VLBA observations at 22 GHz and 43 GHz. X-ray variability is present at time scales of weeks, comparable with the structural changes observed by VLBI. Here we present first results of the high-resolution imaging observations and discuss these findings in the context of the multi-band campaign.
217 - Eduardo Ros 2008
The fine-scale structure and the kinematics of relativistic active galactic nuclei (AGN) jets have been studied by very-long-baseline interferometry at very high resolutions since 1998 at 2 cm wavelength for a sample of over a hundred radio sources ( VLBA 2cm Survey and MOJAVE programs). Since 2007, this is being complemented by the TANAMI project, based on southern observations with the Australian LBA at 3.6 cm and 1.1 cm wavelengths. From our observation campaign, we find that most of the radio jets show linear morphologies at parsec-scales, but some of show curvature and non-radial motions. Features are observed to move at highly relativistic speeds, with Lorentz factors extending above values of 30. We also provide a brief description of the relationship of our radio findings with the AGN observations by the new Fermi Gamma-ray Space Telescope.
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