Line shifts and sub-pc super-massive binary black holes

TL;DR

This paper explores the potential for detecting super-massive binary black holes through shifts in broad emission lines, modeling how these shifts relate to black hole masses and system dynamics.

Contribution

It introduces a simulation-based model linking broad line shifts to black hole masses and binary parameters, aiding in SMBBH detection.

Findings

Peak line shifts depend on black hole masses and system kinematics.

Line shifts are influenced by individual black hole masses and their mass ratio.

Simulation results suggest observable signatures for SMBBH detection.

Abstract

Here we discuss the possibility of super-massive binary black hole (SMBBH) detection, using the shifts of the broad lines emitted from a binary system. We perform a number of simulations of shapes and shifts of $H_{\beta}$ lines emitted from SMBBHs, taking into account the emission from two different regions located around both black holes, and kinematical effects which should be present in a SMBBH. In the model we connect the parameters of the lines with the mass of black holes and find that the peak shift depends, not only on kinematical effects of system rotation and black hole mass ratio, but it is also a function of the individual masses of the two black holes (BHs).