Browsing Research publications by Author "Valtaoja, E."

Now showing items 1-6 of 6

    • A Comparison of the Radio / Submillimetre Spectra of Bl-Lacertae Objects and Flat Spectrum Radio Quasars 

      Gear, W.K.; Stevens, Jason; Hughes, D.H.; Litchfield, S.J.; Robson, E.I.; Terasranta, H.; Valtaoja, E.; Steppe, H.; Aller, M. F.; Aller, H. D. (1994-03-01)
      We present quasi-simultaneous radio, millimetre and submillimetre spectra of 22 BL Lac objects and 24 radio-loud, violently variable quasars. These data are used to test the hypothesis that BL Lacs and OVV quasars are ...

    • Multifrequency observations of blazars. 5: Long-term millimeter, submillimeter, and infrared monitoring 

      Stevens, Jason; Litchfield, S.J.; Robson, E.I.; Hughes, D.H.; Gear, W.K.; Terasranta, H.; Valtaoja, E.; Tornikoski, M. (1994-12-01)
      Multifrequency monitoring data are presented for 17 blazars between 375 and 22 GHz. These data are used to study the overall flaring behavior of blazars, and, in particular, to test predictions of shock models for the early ...

    • Multiwavelength Observations of a Dramatic High-Energy Flare in the Blazar 3C 279 

      Wehrle, A. E.; Pian, E.; Urry, C.M.; Maraschi, L.; McHardy, I.M.; Lawson, A.J.; Ghisellini, G.; Hartman, R.C.; Madejski, G.M.; Makino, F.; Marscher, A.P.; Wagner, S.J.; Webb, J.R.; Aldering, G.S.; Aller, M.F.; Aller, H.D.; Backman, D.E.; Balonek, T.J.; Boltwood, P.; Bonnell, J.; Caplinger, J.; Celotti, A.; Collmar, W.; Dalton, J.; Drucker, A.; Falomo, R.; Fichtel, C.E.; Freudling, W.; Gear, W.K.; Gonzalez-Perez, N.; Hall, P.; Inoue, H.; Johnson, W.N.; Kazanas, D.; Kidger, M.R.; Kii, T.; Kollgaard, R.I.; Kondo, Y.; Kurfess, J.; Lin, Y.C.; McCollum, B.; McNaron-Brown, K.; Nagase, F.; Nair, A.D.; Penton, S.; Pesce, J.E.; Pohl, M.; Raiteri, C.M.; Renda, M.; Robson, E.I.; Sambruna, R.M.; Schirmer, A.F.; Shrader, C.; Sikora, M.; Sillanpaeae, A.; Smith, P.S.; Stevens, Jason; Stocke, J.; Takalo, L.O.; Teraesranta, H.; Thompson, D.J.; Thompson, R.; Tornikoski, M.; Tosti, G.; Treves, A.; Turcotte, P.; Unwin, S.C.; Valtaoja, E.; Villata, M.; Xu, W.; Yamashita, A.; Zook, A. (1998-04-01)
      The blazar 3C 279, one of the brightest identified extragalactic objects in the γ-ray sky, underwent a large (factor of ~10 in amplitude) flare in γ-rays toward the end of a 3 week pointing by Compton Gamma Ray Observatory ...

    • Multiwavelength observations of the February 1996 high-energy flare in the blazar 3C 279 

      Wehrle, A. E.; Pian, E.; Urry, C.M.; Maraschi, L.; Ghisellini, G.; Hartman, R.C.; Madejski, G. M.; Makino, F.; Marscher, A.P.; McHardy, I.M.; Webb, J. R.; Aldering, G. S.; Aller, M. F.; Aller, H. D.; Backman, D.E.; Balonek, T.J.; Boltwood, P.; Bonnell, J.; Caplinger, J.; Celotti, A.; Collmar, W.; Dalton, J.; Drucker, A.; Falomo, R.; Fichtel, C.E.; Freudling, W.; Gear, W.K.; Gonzalez-Perez, N.; Hall, P.; Inoue, H.; Johnson, W. N.; Kidger, M. R.; Kollgaard, R. I.; Kondo, Y.; Kurfess, J.; Lawson, A.J.; McCollum, B.; McNaron-Brown, K.; Nair, D.; Penton, S.; Pesce, J. E.; Pohl, M.; Raiteri, C.M.; Renda, M.; Robson, E.I.; Sambruna, R.M.; Schirmer, A. F.; Shrader, C.; Sikora, M.; Sillanpää, A.; Smith, P.S.; Stevens, Jason; Stocke, J.; Takalo, L.O.; Teräsranta, H.; Thompson, D.J.; Thompson, R.; Tornikoski, M.; Tosti, G.; Turcotte, P.; Treves, A.; Unwin, S.C.; Valtaoja, E.; Villata, M.; Wagner, S.J.; Xu, W.; Zook, A. C. (American Institute of Physics (AIP), 1997-05-01)
      We report CGRO, RXTE, ASCA, ROSAT, IUE, HST and ground-based observations of a large flare in 3C 279 in February 1996. X-rays and γ-rays peaked simultaneously (within one day). We show simultaneous spectral energy distributions ...

    • The Spectral Evolution of High-Frequency Radio Outbursts in the Blazar PKS:0420-014 

      Stevens, Jason; Litchfield, S. J.; Robson, E. I.; Gear, W. K.; Terasranta, H.; Tornikoski, M.; Valtaoja, E. (1995-08-01)
      Multifrequency monitoring data between 375 and 22 GHz are used to investigate spectral evolution of radio outbursts in the blazar 0420-014. It is shown that, after subtraction of the underlying `quiescent' emission, the ...

    • Synchrotron flaring in the jet of 3C 279 

      Lindfors, E.J.; Turler, M.; Valtaoja, E.; Aller, H.; Aller, M.; Mazin, D.; Raiteri, C.M.; Stevens, J. A.; Tornikoski, M.; Tosti, G.; Villata, M. (2006)