Fitting along the Fundamental Plane: New comparisons of jet physics across the black hole mass scale

Correlations between the radio and X-ray bands in the hard state of black hole X-ray
binaries (BHBs) have led to the discovery of the Fundamental Plane of black hole accretion,
linking accretion-driven radiative attributes to black hole mass. Although this discovery has
led to new constraints on radiative efficiencies, there is still significant degeneracy in terms
of understanding the governing physics. I present several new results exploring the processes
driving the Fundamental Plane over the black hole mass range. These include the first ever
homogeneous fits of sources at approximately the same Eddington luminosity but millions of
times different in mass, which I focus on for this proceeding article.