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arXiv · 2502.05697

Exploring the disc-jet scenario in 3C 273 using simultaneous XMM-Newton and NuSTAR observations

Ashwani Pandey·Santanu Mondal·Paul J. Wiita
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Abstract

Context: 3C 273, a well-studied active galactic nucleus (AGN), displays characteristics of both jetted-AGN and Seyfert galaxies, making it an excellent source to study the disc-jet connection in AGN. Aims: To investigate the disk-jet scenario in 3C 273 using broadband (0.3--78 keV) X-ray spectra from {\it XMM-Newton} and {\it NuSTAR}. Methods: We used simultaneous {\it XMM-Newton} and {\it NuSTAR} observations of 3C 273 carried out between 2012 and 2024. The 0.3--78 keV X-ray spectra were first fit with a simple power-law (PL) and then with the accretion-ejection-based JeTCAF model. The JeTCAF model accounts for emission from the jet, extending up to the sonic surface. In this framework, a reflection hump above 10 keV can also arise due to the bulk motion Comptonization of coronal photons by the jet. Results: We found that the simple PL did not provide a good fit, leaving significant residuals at energies below 1.5 keV. All the spectra were fitted well by the JeTCAF model. The weighted-averaged black hole mass of (7.77$\pm$0.30) $\times 10^8 M_\odot$ obtained from the JeTCAF model is comparable with the previous estimates based on reverberation mapping observations and accretion disk models. Conclusions: The 0.3--78 keV X-ray emission of 3C 273 can be fit by the accretion-ejection-based model in which the corona and the jet on top of it make significant contributions to the X-ray flux. The Doppler boosting factor estimated from the jet flux ranges from 1.6 to 2.2, consistent with the lower limit from the literature.

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Ashwani Pandey, Santanu Mondal, Paul J. Wiita. 2025-02-08. Exploring the disc-jet scenario in 3C 273 using simultaneous XMM-Newton and NuSTAR observations. https://doi.org/10.1051/0004-6361%2F202451840

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