The Accelerating Jet of 3C 279

Thumbnail Image
Publication date
Reading date
Bloom, S.D.
Fromm, Christian M.
Ros Ibarra, Eduardo
Journal Title
Journal ISSN
Volume Title
Analysis of the proper motions of the sub-parsec scale jet of the quasar 3C 279 at 15 GHz with the VLBA shows significant accelerations in four of nine superluminal features. Analysis of these motions is combined with the analysis of flux density light curves to constrain values of Lorentz factor and viewing angle (and their derivatives) for each component. The data for each of these components is consistent with significant changes to the Lorentz factor, viewing angle and azimuthal angle, suggesting jet bending with changes in speed. We see that for these observed components Lorentz factors are in the range Γ = 10−41, viewing angles are in the range ϑ = 0.1◦ −5.0◦ , and intrinsic (source frame) flux density is in the range, Fν , int = 1.5×10−9−1.5×10−5 Jy. Considering individual components, the Lorentz factors vary from Γ = 11 − 16 for C1, Γ = 31 − 41 for C5, Γ = 29 − 41 for C6 and Γ = 9 − 12 for C8, indicating that there is no single underlying flow speed to the jet and likely we are seeing pattern speeds from shocks in the jet. The viewing angles vary in time from 0.6◦ to 1.5◦ in the case of C1 (the least extreme example), vary from 0.5◦ to 5.0◦ in the case of C8 and vary from 0.1◦ to 0.9◦ for C5 (the last two being the most extreme examples). The intrinsic flux density varies by factors from 1.4 for C8 and 430 for C5. Theoretical analysis of the accelerations also indicates potential jet bending. In addition, for one component, C5, polarization measurements also set limits to the trajectory of the jet.
Bibliographic reference
Bloom, S.D. Fromm, Christian M. Ros Ibarra, Eduardo 2013 The Accelerating Jet of 3C 279 Astronomical Journal 145 12 1 10