An eccentric binary blackhole in post-Newtonian theory

Abstract: Gravitational waves radiated during binary black hole coalescence is a perfect probe for studying the characteristics of strong gravity. Advanced techniques for creating numerical relativity substitute models for eccentric binary black hole systems are presumed to become more crucial in existing and anticipated gravitational wave detectors. The imprint on the observation data of the gravitational wave emitted by the binary coalescence enhances the two body system studies. The aim of this study is to present an overview of the change in characteristics behaviours of hierarchical massive astrophysical objects merger, which are the data bank of the early universe. We present results from numerical relativity simulations of equal-mass and unequal mass nonspinning inspiral binary-black-hole system in the Post Newtonian framework. We also consider the time evolution of eccentricity for the initial eccentric system. The eccentric Post Newtonian equations are expanded in the form of frequency related variable $x = (M \omega)^{2/3}$. The model is restricted to the (2, 2) spin-weighted spherical harmonic modes. We conclude that for higher eccentricity as well as mass ratio there exist higher oscillation in orbital radius and in eccentricity.