The Quasar SDSS J1536+0441: An Unusual Double-Peaked Emitter

Understand

The quasar SDSS J153636.22+044127.0, exhibiting peculiar broad emission-line profiles with multiple components, was proposed as a candidate sub-parsec binary supermassive black hole system.

• More recently, imaging revealed two spatially distinct sources, leading some to suggest the system to be a quasar pair separated by ~5 kpc.
• We present Palomar and Keck optical spectra of this system from which we identify a third velocity component to the emission lines.
• We argue that the system is more likely an unusual member of the class of active galactic nuclei (AGNs) known as "double-peaked emitters" than a sub-parsec black hole binary or quasar pair.