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arXiv · 0907.5414

Probing the nature of the massive black hole binary candidate SDSS J1536+0441

R. Decarli·M. Dotti·R. Falomo·A. Treves·M. Colpi·J. K. Kotilainen·C. Montuori·M. Uslenghi
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Abstract

We present an imaging study of the black hole binary candidate SDSS J1536+0441 (z=0.3893), based on deep, high resolution VzK images collected at the ESO/VLT. The images clearly show an asymmetric elongation, indicating the presence of a companion source at ~1" (~5 kpc projected distance) East from the quasar. The host galaxy of the quasar is marginally resolved. We find that the companion source is a luminous galaxy, the light profile of which suggests the presence of an unresolved, faint nucleus (either an obscured AGN or a compact stellar bulge). The study of the environment around the quasar indicates the occurrence of a significant over-density of galaxies with a redshift compatible with z~0.4. This suggests that it resides in a moderately rich cluster of galaxies.

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R. Decarli, M. Dotti, R. Falomo, A. Treves, M. Colpi, J. K. Kotilainen, C. Montuori, M. Uslenghi. 2009-07-30. Probing the nature of the massive black hole binary candidate SDSS J1536+0441. https://doi.org/10.1088/0004-637x/703/1/l76

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