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Detectability of gravitational effects of supernova neutrino emission through pulsar timing

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 Added by Ken D. Olum
 Publication date 2013
  fields Physics
and research's language is English




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Core-collapse supernovae emit on the order of 3x10^53 ergs in high-energy neutrinos over a time of order 10 seconds, and so decrease their mass by about 0.2 solar mass. If the explosion is nearly spherically symmetric, there will be little gravitational wave emission. Nevertheless, the sudden decrease of mass of the progenitor may cause a change in the gravitational time delay of signals from a nearby pulsar. We calculate the change in arrival times as successive pulses pass through the neutrino shell at different times, and find that the effect may be detectable in ideal circumstances.



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146 - Casey McGrath 2021
Pulsar timing experiments are currently searching for gravitational waves, and this dissertation focuses on the development and study of the pulsar timing residual models used for continuous wave searches. The first goal of this work is to re-present much of the fundamental physics and mathematics concepts behind the calculations and theory used in pulsar timing. While there exist many reference sources in the literature, I try to offer a fully self-contained explanation of the fundamentals of this research which I hope the reader will find helpful. The next goal broadly speaking has been to further develop the mathematics behind the currently used pulsar timing models for detecting gravitational waves with pulsar timing experiments. I classify four regimes of interest, governed by frequency evolution and wavefront curvature effects incorporated into the timing residual models. Of these four regimes the plane-wave models are well established in previous literature. I add a new regime which I label Fresnel, as I show it becomes important for significant Fresnel numbers describing the curvature of the gravitational wavefront. Then I give two in-depth studies. The first forecasts the ability of future pulsar timing experiments to probe and measure these Fresnel effects. The second further generalizes the models to a cosmologically expanding universe, and I show how the Hubble constant can be measured directly in the most generalized pulsar timing residual model. This offers future pulsar timing experiments the possibility of being able to procure a purely gravitational wave-based measurement of the Hubble constant. The final chapter shows the initial steps taken to extend this work in the future toward Doppler tracking experiments.
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