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Chandra Observations of the Cloverleaf Quasar H 1413+117: A Unique Laboratory for Microlensing Studies of a Lobal Quasar

G. Chartas·M. Eracleous·E. Agol·S. C. Gallagher
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Abstract

We present new results uncovered by a re-analysis of a Chandra observation of the gravitationally lensed, low-ionization broad absorption line (LoBAL) quasar H 1413+117. Previous analyses of the same Chandra observation led to the detection of a strong, redshifted Fe Kalpha line from the combined spectrum of all images. We show that the redshifted Fe Kalpha line is only significant in the brighter image A. The X-ray flux fraction of image A is larger by a factor of 1.55 +/- 0.17 than the optical R-band flux fraction, indicating that image A is significantly enhanced in the X-ray band. We also find that the Fe Kalpha line and the continuum are enhanced by different factors. A microlensing event could explain both the energy-dependent magnification and the significant detection of Fe Kalpha line emission in the spectrum of image A only. In the context of this interpretation we provide constraints on the spatial extent of the inferred scattered continuum and reprocessed Fe Kalpha line emission regions in a LoBAL quasar.

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G. Chartas, M. Eracleous, E. Agol, S. C. Gallagher. 2004-01-13. Chandra Observations of the Cloverleaf Quasar H 1413+117: A Unique Laboratory for Microlensing Studies of a Lobal Quasar. https://doi.org/10.1086/382743

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