464 citations · 11.8k across the 199 of their papers we have counts for
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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…
The WEBT Campaign on the Intermediate BL Lac Object 3C66A in 2007-2008
M. Boettcher, K. Fultz
Prompted by a high optical state in September 2007, the Whole Earth Blazar Telescope (WEBT) consortium organized an intensive optical, near-IR (JHK) and radio observing campaign on…
A new activity phase of the blazar 3C 454.3. Multifrequency observations by the WEBT and XMM-Newton in 2007-2008
C. M. Raiteri, M. Villata, V. M. Larionov +2
We present and analyse the WEBT multifrequency observations of 3C 454.3 in the 2007-2008 observing season, including XMM-Newton observations and near-IR spectroscopic monitoring, a…
Testing the inverse-Compton catastrophe scenario in the intra-day variable blazar S5 0716+71, III. Rapid and correlated flux density variability from radio to sub-mm bands
L. Fuhrmann, T. P. Krichbaum, A. Witzel +22
The BL Lac object S5 0716+71 was observed in a global multi-frequency campaign to search for rapid and correlated flux density variability and signatures of an inverse-Compton (IC)…
Long term radio variability of AGN
T. Hovatta, M. Tornikoski, H. J. Lehto +7
A large number of AGN have been monitored for nearly 30 years at 22, 37 and 87 GHz in Metsähovi Radio Observatory. These data were combined with lower frequency 4.8, 8.0 and 14.5 G…
Wavelet analysis of a large sample of AGN at high radio frequencies
T. Hovatta, H. J. Lehto, M. Tornikoski
We have studied the characteristic timescales of 80 AGNs at 22, 37 and 90 GHz examining the properties of the wavelet method and comparing them to traditional Fourier-based methods…