X-Ray Monitoring of Gravitationally Lensed Radio-loud Quasars with Chandra

• Published in: The Astrophysical journal Vol. 894; no. 2; pp. 153 - 172
• Main Authors: Dogruel, Mustafa Burak, Dai, Xinyu, Guerras, Eduardo, Cornachione, Matthew, Morgan, Christopher W.
• Format: Journal Article
• Language: English
• Published: Philadelphia The American Astronomical Society 01.05.2020; IOP Publishing
• Subjects: Astrophysics; Bayesian analysis; Emission; Emission lines; Light curve; Microlenses; Quasar microlensing; Quasars; Radio; Radio loud quasars; Signal to noise ratio; Space telescopes; Spectral analysis; Spectrum analysis; Strong gravitational lensing; Supermassive black holes; X ray sources; X ray telescopes; X-ray active galactic nuclei; X-ray astronomy; X-ray emissions
• ISSN: 0004-637X; 1538-4357
• DOI: 10.3847/1538-4357/ab879b

In this work, we calculated the sizes of unresolved X-ray emission regions in three gravitationally lensed radio-loud quasars, B 1422+231, MG J0414+0534, and Q 0957+561, using a combination of imaging and spectral analysis on the X-ray data taken from the Chandra X-Ray Observatory. We tentatively detected FeK emission lines in MG J0414+0534 and Q 0957+561 with over 95% significance, whereas, we did not significantly detect FeK emission in B 1422+231. We constructed differential microlensing light curves from absorption corrected count rates. We subsequently performed a microlensing analysis on the X-ray microlensing light curves to measure the X-ray source sizes in rest frame soft (0.83-3.6 keV), hard (3.6-21.8 keV), and full (0.83-21.8 keV) bands, based on either Bayesian or maximum likelihood probabilities. For B 1422+231, sizes from the two methods are consistent with each other, (Bayesian), 11.81 3.75 (maximum likelihood), where . However, for MG J0414+0534 and Q 0957+561, the two methods yield substantially different results suggesting that more frequently sampled data with better signal-to-noise ratio are needed to measure the source size for these two objects. Comparing the acquired size values with the radio-quiet sample in the literature we found that our results are consistent with X-ray source size scaling approximately as RX ∝ MBH with the mass of the central supermassive black hole. Our Bayesian analysis results also indicate that radio-loud quasars tend to have larger unresolved X-ray emission sizes compared to the radio-quiet ones, suggesting a more prominent jet contribution.