Exploring Gravitational Wave Signatures from Strongly Magnetized Neutron Star Binaries

We study the impact of eccentricity and strong magnetic fields on gravitational wave generation during the late-stage inspiral of binary neutron star (BNS) systems. While neutron stars are typically observed to exhibit strong magnetic fields ranging from 10¹⁴ to 10¹⁵ G, theoretical models predict magnetic field strengths of up to 10¹⁸ G. BNS systems formed through dynamical capture may retain substantial eccentricity and extreme magnetic fields during the final inspiral stages. These fields can influence orbital dynamics by radiating orbital energy due to magnetic dipoles in motion and through magnetic interactions depending on the relative alignment of the neutron stars’ magnetic axes. Using a perturbative approach, we derive solutions for the equations of motion, total energy loss rate, and phase evolution for such systems. Our findings indicate that dephasing effects caused by magnetic fields on the order of 10¹⁶ G in inspiralling neutron stars can produce sizable contributions to the gravitational wave signal, which could be detected by third-generation gravitational wave detectors. Such observations could provide valuable insights into ultra-strong magnetic fields, magnetar binaries, and their potential formation channels.