SpitzerIRAC Imaging of the Relativistic Jet from Superluminal Quasar PKS 0637-752

Yasunobu Uchiyama, C. Megan Urry, Jeffrey Van Duyne, C. C. Cheung, Rita M. Sambruna, Tadayuki Takahashi, Fabrizio Tavecchio, Laura Maraschi
2005 Astrophysical Journal  
Emission from the relativistic jet located at hundreds of kpc from the core of the superluminal quasar PKS 0637-752 was detected at 3.6 and 5.8 microns with the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. The unprecedented sensitivity and arcsecond resolution of IRAC allows us to explore the mid-infrared emission from kiloparsec-scale quasar jets for the first time. The mid-infrared flux from the jet knots, when combined with radio and optical fluxes, confirms a synchrotron
more » ... s a synchrotron origin of the radio-to-optical emission and constrains very well the high energy end of the nonthermal electron distribution. Assuming the X-rays are produced in the relativistically moving knots via inverse Compton scattering of cosmic microwave background (CMB) radiation, the infrared observation puts constraints on the matter content of the quasar extended jet. Specifically, pure electron-positoron pair jet models are unfavorable based on the lack of an infrared bump associated with "bulk Comptonization" of CMB photons by an ultrarelativistic jet.
doi:10.1086/497426 fatcat:luaxny6mh5cizmp2ryohiobzae