A systematic search for massive black hole binaries in SDSS spectroscopic sample

Understand

We present the results of a systematic search for massive black hole binaries in the Sloan Digital Sky Survey spectroscopic database.

• We focus on bound binaries, under the assumption that one of the black holes is active.
• In this framework, the broad lines associated to the accreting black hole are expected to show systematic velocity shifts with respect to the narrow lines, which trace the rest-frame of the galaxy.
• For a sample of 54586 quasars and 3929 galaxies at redshifts 0.1<z<1.5 we brute-force model each spectrum as a mixture of two quasars at two different redshifts.