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arXiv · 2406.06743

Gravitational Radiation Power Spectrum of Garfinkle-Vachaspati Cosmic String Loops

S. David Storm·Robert J. Scherrer
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Abstract

We examine the power spectrum $P_n$ of the $n$th harmonic for Garfinkle-Vachaspati cosmic strings, which correspond to planar rectangular loops. While these loop tractories are self-intersecting, a slightly perturbed non-self-intersecting form of these trajectories has been suggested as a generic end state of cosmic string loop fragmentation. We find that $P_n$ scales as $n^{-2} \ln n$, rather than the expected $n^{-2}$ for kink-kink collisions. This result is demonstrated analytically for even $n$ in square loops and numerically for all other cases. At lowest order, the effect of loop decays is to further enhance $P_n$ at large $n$ relative to its value at small $n$. The consequences for relic stochastic background radiation along with the caveats pertaining to our results are discussed.

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S. David Storm, Robert J. Scherrer. 2024-06-10. Gravitational Radiation Power Spectrum of Garfinkle-Vachaspati Cosmic String Loops. https://arxiv.org/abs/2406.06743

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