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ABSTRACT Neutron stars in astrophysical binary systems represent exciting sources for multimessenger astrophysics. A potential source of electromagnetic transients from compact binary systems is the neutron star ocean, the external fluid layer encasing a neutron star. We present a groundwork study into tidal waves in neutron star oceans and their consequences. Specifically, we investigate how oscillation modes in neutron star oceans can be tidally excited during compact binary inspirals and parabolic encounters. We find that neutron star oceans can sustain tidal waves with frequencies between 0.01 and 20 Hz. Our results suggest that tidally resonant neutron star ocean waves may serve as a never-before studied source of precursor electromagnetic emission prior to neutron star–black hole and binary neutron star mergers. If accompanied by electromagnetic flares, tidally resonant neutron star ocean waves, whose energy budget can reach 1046 erg, may serve as early warning signs (≳1 min before merger) for compact binary mergers. Similarly, excited ocean tidal waves will coincide with neutron star parabolic encounters. Depending on the neutron star ocean model and a flare emission scenario, tidally resonant ocean flares may be detectable by Fermi and Nuclear Spectroscopic Telescope Array (NuSTAR) out to ≳100 Mpc with detection rates as high as ∼7 yr−1 for binary neutron stars and ∼0.6 yr−1 for neutron star–black hole binaries. Observations of emission from neutron star ocean tidal waves along with gravitational waves will provide insight into the equation of state at the neutron star surface, the composition of neutron star oceans and crusts, and neutron star geophysics.
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Design of an optimized nested-mirror neutron reflector for a NNBAR experiment
Conceptual design of a nested mirror assembly for neutron anti-neutron oscillation measurements is presented, with the specific focus of potential advantages for fabrication of large-scale optics.
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- Award ID(s):
- 2209590
- PAR ID:
- 10527646
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Esevier (Nuclear Instruments and Methods in Physics Research A)
- Date Published:
- Journal Name:
- Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
- Edition / Version:
- 1
- Volume:
- 1051
- Issue:
- C
- ISSN:
- 0168-9002
- Page Range / eLocation ID:
- 168235
- Subject(s) / Keyword(s):
- fundamental neutron physics, fundamental symmetries, baryon number violation, particle physics, neutron optics
- Format(s):
- Medium: X Size: 2.66 Mb Other: pdf
- Size(s):
- 2.66 Mb
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1016/j.nima.2023.168235
