Polarization Survey of Supermassive Black Hole Binary Candidates

Supermassive black hole binaries (SMBHBs) are a direct consequence of hierarchical structure formation and hence should be a common occurrence in galactic nuclei. However, so far they have proven surprisingly elusive. Although several candidates have been identified through the periodic signals possibly induced in their light curves due to the orbital motion of the SMBHB, we still lack any confirmed detection. Here we propose a pilot study of candidate SMBHBs that will allow us to detect optical polarization modulation, a unique signature induced by the orbital motion and a clear smoking gun for the presence of the binary. The subset of candidates we propose to follow-up have additional evidence for their binary nature (beyond the optical periodicity), since their multi-wavelength variability is consistent with Doppler boost produced from the relativistic orbital velocities in a binary system.

Monitoring program

The OB generator will be used to request all ToO observations. Scripts to perform all the requested operations will be automatically created and placed in the directory ~/scripts/65-014/. An email will be sent automatically to the observer, which contains all the information about the requested observations, the names and locations of the scripts, instructions for observing and comments from the creator of the trigger.
To summarise:

Go to the directory
  cd ~/scripts/65-014
List the available scripts
  ls -lrt

and execute the OB generated scripts requested in the trigger email.

Targets