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Title: Gamma-radiation sky maps from compact binaries
Abstract We study sky maps and light curves of gamma-ray emission from neutron stars in compact binaries, and in isolation. We briefly review some gamma-ray emission models, and reproduce sky maps from a standard isolated pulsar in the Separatrix Layer model. We consider isolated pulsars with several variations of a dipole magnetic field, including superpositions, and predict their gamma-ray emission. Our results provide new heuristics on what can and cannot be inferred about the magnetic field configuration of pulsars from high-energy observations. We find that typical double-peak light curves can be produced by pulsars with significant multipole structure beyond a single dipole. For binary systems, we also present a simple approximation that is useful for rapid explorations of binary magnetic field structure. Finally, we predict the gamma-ray emission pattern from a compact black hole-neutron star binary moments before merger by applying the Separatrix Layer model to data simulated in full general relativity; we find that face-on observers receive little emission, equatorial observers see one broad peak, and more generic observers typically see two peaks.  more » « less
Award ID(s):
2011383
PAR ID:
10332665
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Journal of Cosmology and Astroparticle Physics
Volume:
2022
Issue:
02
ISSN:
1475-7516
Page Range / eLocation ID:
027
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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