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arXiv · 1106.6052

Discovery of Energy Dependent X-ray Microlensing in Q2237+0305

Bin Chen·Xinyu Dai·Christopher S. Kochanek·George Chartas·Jeffrey A. Blackburne·Szymon Kozlowski
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Abstract

We present our long term Chandra X-ray monitoring data for the gravitationally lensed quasar Q2237+0305 with 20 epochs spanning 10 years. We easily detect microlensing variability between the images in the full (0.2--8 keV), soft (0.2--2 keV), and hard (2--8 keV) bands at very high confidence. We also detect, for the first time, chromatic microlensing differences between the soft and hard X-ray bands. The hard X-ray band is more strongly microlensed than the soft band, suggesting that the corona above the accretion disk thought to generate the X-rays has a non-uniform electron distribution, in which the hotter and more energetic electrons occupy more compact regions surrounding the black holes. Both the hard and soft X-ray bands are more strongly microlensed than the optical (restframe UV) emission, indicating that the X-ray emission is more compact than the optical, confirming the microlensing results from other lenses.

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Bin Chen, Xinyu Dai, Christopher S. Kochanek, George Chartas, Jeffrey A. Blackburne, Szymon Kozlowski. 2011-06-29. Discovery of Energy Dependent X-ray Microlensing in Q2237+0305. https://doi.org/10.1088/2041-8205%2F740%2F2%2Fl34

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