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Title: Fresnel models for gravitational wave effects on pulsar timing
ABSTRACT Merging supermassive black hole binaries produce low-frequency gravitational waves, which pulsar timing experiments are searching for. Much of the current theory is developed within the plane-wave formalism, and here we develop the more general Fresnel formalism. We show that Fresnel corrections to gravitational wave timing residual models allow novel measurements to be made, such as direct measurements of the source distance from the timing residual phase and frequency, as well as direct measurements of chirp mass from a monochromatic source. Probing the Fresnel corrections in these models will require future pulsar timing arrays with more distant pulsars across our Galaxy (ideally at the distance of the Magellanic Clouds), timed with precisions less than 100 ns, with distance uncertainties reduced to the order of the gravitational wavelength. We find that sources with chirp mass of order 109 M⊙ and orbital frequency ω0 > 10 nHz are good candidates for probing Fresnel corrections. With these conditions met, the measured source distance uncertainty can be made less than 10 per cent of the distance to the source for sources out to ∼100 Mpc, source sky localization can be reduced to sub-arcminute precision, and source volume localization can be made to less than 1 Mpc3 for sources out more » to 1-Gpc distances. « less
Authors:
;
Award ID(s):
1912649
Publication Date:
NSF-PAR ID:
10253440
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
505
Issue:
3
Page Range or eLocation-ID:
4531 to 4554
ISSN:
0035-8711
Sponsoring Org:
National Science Foundation
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