438 citations · 2.5k across the 39 of their papers we have counts for
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Multi-frequency VLBA study of the blazar S5 0716+714 during the active state in 2004: I. Inner jet kinematics
E. A. Rastorgueva, K. Wiik, T. Savolainen +4
We observed the blazar \object{0716+714} with the VLBA during its active state in 2003-2004. In this paper we discuss multi-frequency analysis of the inner jet (first 1 mas) kinema…
Studying the continuum spectrum of the parsec scale jets by multi-frequency VLBI measurements
T. Savolainen, K. Wiik, E. Valtaoja +1
Multi-frequency VLBI observations allow studies of the continuum spectrum in the different parts of the parsec scale jets of AGN, providing information on the physical properties o…
Doppler factors, Lorentz factors and viewing angles for quasars, BL Lacertae objects and radio galaxies
T. Hovatta, E. Valtaoja, M. Tornikoski +1
We have calculated variability Doppler boosting factors, Lorentz factors, and viewing angles for a large sample of sources by using total flux density observations at 22 and 37 GHz…
Long-term radio variability of AGN: flare characteristics
T. Hovatta, E. Nieppola, M. Tornikoski +3
We have studied the flare characteristics of 55 AGN at 8 different frequency bands between 4.8 and 230 GHz. Our extensive database enables us to study the various observational pro…
Blazar sequence - an artefact of Doppler boosting
E. Nieppola, E. Valtaoja, M. Tornikoski +2
The blazar sequence is a scenario in which the bolometric luminosity of the blazar governs the appearance of its spectral energy distribution. The most prominent result is the sign…
Magnetic Field Structure in the Parsec Scale Jet of 3C273 from Multifrequency VLBA Observations
T. Savolainen, K. Wiik, E. Valtaoja +1
We present first results from a multifrequency VLBA observations of 3C273 in 2003. The source was observed simultaneously at 5.0, 8.4, 15.3, 22.2, 43.2 and 86.2 GHz, and from this…