2019/04/30 by Mor Rozner, Evgeni Grishin, Yonadav Barry Ginat +2 · 2 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Axion #Binary number #Binary pulsar #Dark Matter and Cosmic Phenomena #Eccentricity (behavior) #Pulsar #Pulsars and Gravitational Waves Research #Range (aeronautics) #Scaling #astro-ph.CO #astro-ph.HE #gr-qc
paper · pdf · doi:10.1088/1475-7516/2020/03/061
Published in JCAP
openalex created_date 2019/04/11 · arxiv created 2020/03/30 · openalex publication_date 2020/03/30 · arxiv updated 2020/03/31 · openalex updated_date 2026/08/05
We investigate the extent to which resonances between an oscillating background of ultra-light axion and a binary Keplerian system can affect the motion of the latter. These resonances lead to perturbations in the instantaneous time-of-arrivals, and to secular variations in the period of the binary. While the secular changes at exact resonance have recently been explored, the instantaneous effects have been overlooked. In this paper, we examine the latter using N-body simulations including the external oscillatory forcing induced by the axion background. While the secular effects are restricted to a narrow width near the resonance, the instantaneous changes, albeit strongest close to resonances, are apparent for wide range of configurations. We compute the signal-to-noise ratio (SNR) as a function of semi-major axis for a detection of axion oscillations through the RØmer delay. The latter can be extracted from the time-of-arrivals of binary pulsars. The SNR broadly increases with increasing binary eccentricity as expected from secular expectations. However, we find that it differs significantly from the scaling a 5/2 around the lowest orders of resonance. Future observations could probe these effects away from resonances and, therefore, constrain a much broader range of axion masses provided that binary pulsar systems are found near the central region of our Galaxy, and that the time-or-arrival measurement accuracy reaches ≲ 10 ns.