Binary Love Relation for the Inspiral of Heavy Neutron Stars*

Because of recent measurements of heavy neutron stars of at least 2 solar masses, there appears to be a strong preference for equations of state of neutron stars that have a sharp rise in the speed of sound as a function of baryon number density above the conformal limit.  It was shown in [1] that the Binary Love relation depends on a specific feature of the EoS, which is the baryon number density at which the rise in the speed of sound occurs.  Specifically, it was found that one could measure a change in the slope of the Binary Love relation. Here we use a modified Gaussian process to study ~100K equations of state with sharp rises in the speed of sound to study the connection between the rise in the speed of sound and the slope change in the binary love relation.

[1] H. Tan, et al, Phys.Rev.Lett. 128 (2022) 16, 161101