High-Order Multipole and Binary Love Number Universal Relations

Using a data set of approximately 2 million phenomenological equations state consistent with observational constraints, we construct new equation-of-state-insensitive universal relations that exist between the multipolar tidal deformability parameters neutron stars, $\Lambda_l$, for several high-order multipoles ($l = 5,6,7,8$). We confirm existence relation radius $1.4 M_\odot$ NS, $R_{1.4}$ and reduced parameter binary, $\tilde{\Lambda}$, chirp mass. extend this to large number masses radii isolated NSs different mass $M$, $R_M$. find there is an optimal value $M$ every $\mathcal{M}$ such uncertainty in estimate $R_M$ minimized when using relation. discuss utility implications these upcoming LIGO O4 run third-generation detectors.