Chandra X-Ray Imaging and an Inverse Compton/Cosmic Microwave Background Model for the Inner Jet of PKS 0637–752
- 1Center for Astrophysics ∣ Harvard & Smithsonian
- 2University of Bristol
- 3National Centre for Radio Astrophysics
Abstract
We present the X-ray surface brightness maps of the jet from the quasar PKS 0637−752, using two epochs of archival Chandra observations (1999 and 2017). We present, for the first time, a model of the faint inner jet extending from 3 . ″ 4 to 7″ from the core, interpreting its X-ray emission as inverse Compton (CMB) scattering of cosmic microwave background photons by the synchrotron-emitting relativistic electrons. The inner jet contrasts with the bright outer part of the jet, dominated by several discrete knots for which upper limits to the Fermi gamma-ray flux rule out the CMB mechanism. It is the first detailed CMB model published for this inner jet. We examine three physically motivated scenarios, distinguished by the high-energy cutoff of the electron distribution, that can account for the observed radio, millimeter/submillimeter, and X-ray emission while remaining consistent with optical and gamma-ray upper limits. We also report for the first time X-rays from the radio lobe at the end of the receding jet.
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BibTeX
@article{maithil2026chandra,
title = {{Chandra X-Ray Imaging and an Inverse Compton/Cosmic Microwave Background Model for the Inner Jet of PKS 0637–752}},
author = {Jaya Maithil and Daniel A. Schwartz and Aneta Siemiginowska and Diana M. Worrall and Preeti Kharb},
journal = {The Astrophysical Journal},
year = {2026},
month = oct,
doi = {10.3847/1538-4357/aea562},
url = {https://iopscience.iop.org/article/10.3847/1538-4357/aea562},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Chandra X-Ray Imaging and an Inverse Compton/Cosmic Microwave Background Model for the Inner Jet of PKS 0637–752
AU - Jaya Maithil
AU - Daniel A. Schwartz
AU - Aneta Siemiginowska
AU - Diana M. Worrall
AU - Preeti Kharb
PY - 2026
DA - 2026/10/21
JO - The Astrophysical Journal
DO - 10.3847/1538-4357/aea562
UR - https://iopscience.iop.org/article/10.3847/1538-4357/aea562
AB - We present the X-ray surface brightness maps of the jet from the quasar PKS 0637−752, using two epochs of archival Chandra observations (1999 and 2017). We present, for the first time, a model of the faint inner jet extending from 3 . ″ 4 to 7″ from the core, interpreting its X-ray emission as inverse Compton (CMB) scattering of cosmic microwave background photons by the synchrotron-emitting relativistic electrons. The inner jet contrasts with the bright outer part of the jet, dominated by several discrete knots for which upper limits to the Fermi gamma-ray flux rule out the CMB mechanism. It is the first detailed CMB model published for this inner jet. We examine three physically motivated scenarios, distinguished by the high-energy cutoff of the electron distribution, that can account for the observed radio, millimeter/submillimeter, and X-ray emission while remaining consistent with optical and gamma-ray upper limits. We also report for the first time X-rays from the radio lobe at the end of the receding jet.
SN - 0004-637X
SN - 1538-4357
ER -