An HST Proper-Motion Study of the Large-scale Jet of 3C273

Abstract

The radio galaxy 3C 273 hosts one of the nearest and best-studied powerful quasar jets. Having been imaged repeatedly by the Hubble Space Telescope (HST) over the past twenty years, it was chosen for an HST program to measure proper motions in the kiloparsec-scale resolved jets of nearby radio-loud active galaxies. The jet in 3C 273 is highly relativistic on sub-parsec scales, with apparent proper motions up to 15$c$ observed by VLBI (Lister et al., 2013). In contrast, we find that the kpc-scale knots are compatible with being stationary, with a mean speed of $-$0.2$\pm$0.5$c$ over the whole jet. Assuming the knots are packets of moving plasma, an upper limit of 1c implies a bulk Lorentz factor $\Gamma <$2.9. This suggests that the jet has either decelerated significantly by the time it reaches the kpc scale, or that the knots in the jet are standing shock features. The second scenario is incompatible with the inverse Compton off the Cosmic Microwave Background (IC/CMB) model for the X-ray emission of these knots, which requires the knots to be in motion, but IC/CMB is also disfavored in the first scenario due to energetic considerations, in agreement with the recent finding of Meyer & Georganopoulos (2014) which ruled out the IC/CMB model for the X-ray emission of 3C 273 via gamma-ray upper limits.

13 pages, 8 figures, 1 appendix. Accepted for publication in the Astrophysical Journal

References in corpus (11)

• The power of relativistic jets is larger than the luminosity of their accretion disks
• Sub-milliarcsecond Imaging of Quasars and Active Galactic Nuclei III. Kinematics of Parsec-Scale Radio Jets
• Dynamics and High Energy Emission of the Flaring HST-1 Knot in the M 87 Jet
• Superluminal Radio Features in the M87 Jet and the Site of Flaring TeV Gamma-ray Emission
• New Chandra observations of the jet in 3C273. I. Softer X-ray than radio spectra and the X-ray emission mechanism
• MOJAVE XII: Acceleration and Collimation of Blazar Jets on Parsec Scales
• Shedding New Light on the 3C 273 Jet with the Spitzer Space Telescope
• The radio-ultraviolet spectral energy distribution of the jet in 3C273
• Ruling out IC/CMB X-rays in PKS 0637-752 and the Implications for TeV Emission from Large-Scale Quasar Jets
• Quasar X-ray jets: Gamma-ray diagnostics of the synchrotron and inverse Compton hypotheses, the case of 3C 273
• An asymmetrical synchrotron model for knots in the 3C 273 jet

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