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Context.The well-studied active galactic nucleus (AGN) 3C 273 displays characteristics of both jetted-AGNs and Seyfert galaxies, which makes it an excellent source to study the disc-jet connection in AGNs. Aims.We aim to investigate the disc-jet scenario in 3C 273 using broad-band (0.3–78 keV) X-ray spectra fromXMM-NewtonandNuSTAR. Methods.We used simultaneousXMM-NewtonandNuSTARobservations of 3C 273 carried out between 2012 and 2024. The 0.3–78 keV X-ray spectra were first fitted with a simple power law (PL) and then with the accretion-ejection-basedJeTCAFmodel. TheJeTCAFmodel accounts for emission from the jet, which extends 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 find 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 theJeTCAFmodel. The weighted-averaged black hole mass of (7.77 ± 0.30) × 108 M⊙obtained from theJeTCAFmodel is comparable with the previous estimates based on reverberation mapping observations and accretion disc 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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Confronting a Thin Disk-wind Launching Mechanism of Broad-line Emission in Active Galactic Nuclei with GRAVITY Observations of Quasar 3C 273
Abstract Quasars show a remarkable degree of atomic emission-line broadening, an observational feature which, in conjunction with a radial distance estimate for this emission from the nucleus, is often used to infer the mass of the central supermassive black hole. The radius estimate depends on the structure and kinematics of this so-called broad-line region, which is often modeled as a set of discrete emitting clouds. Here, we test an alternative kinematic disk-wind model of optically thick line emission originating from a geometrically thin accretion disk under Keplerian rotation around a supermassive black hole. We use this model to calculate broad emission-line profiles and interferometric phases to compare to GRAVITY data and previously published cloud modeling results. While we show that such a model can provide a statistically satisfactory fit to GRAVITY data for quasar 3C 273, we disfavor it as it requires 3C 273 be observed at high inclination, which observations of the radio jet orientation do not support.
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- Award ID(s):
- 1909711
- PAR ID:
- 10442884
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 953
- Issue:
- 2
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 184
- Size(s):
- Article No. 184
- Sponsoring Org:
- National Science Foundation
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