The cusp properties of High Harmonic Loops

Abstract

In determining the gravitational signal of cusps from a network of cosmic strings loops, a number of key parameters have to be assumed. These include the typical number of cusps per period of string oscillation and the typical values of the sharpness parameters of left and right moving waves on the string, evaluated at the cusp event. Both of these are important, as the power stored in the gravitational waves emitted from the loops of string is proportional to the number of cusps per period, and inversely proportional to the product of the sharpness parameters associated with the left and right moving modes on the string. In suitable units both of these quantities are usually thought to be of order unity. In order to try and place these parameters on a more robust footing, we analyse in detail a large number of randomly chosen loops of string that can have high harmonics associated with them, such as one might expect to form by chopping off an infinite string in the early universe. This allows us to analyse tens of thousands of loops and obtain detailed statistics on these crucial parameters. While we find in general the sharpness parameters are indeed close to unity, as assumed in previous work (with occasional exceptions where they can become $O(10^{-2})$), the cusp number per period scales directly with the number of harmonics on the loop and can be significantly larger than unity. This opens up the possibility of larger signals than would have otherwise been expected, potentially leading to tighter bounds on the dimensionless cosmic string tension $G\mu$.

arXiv comment17 pages, 8 figures

References in corpus (51)

• Observation of Gravitational Waves from a Binary Black Hole Merger
• Planck 2015 results. XIII. Cosmological parameters
• Cosmic strings
• Towards Inflation in String Theory
• False Vacuum Inflation with Einstein Gravity
• Brane Inflation
• The Inflationary Brane-Antibrane Universe
• Gravitational radiation from cosmic (super)strings: bursts, stochastic background, and observational windows
• CMB Anisotropies: Total Angular Momentum Method
• Gravitational wave bursts from cosmic strings
• Gravitational wave bursts from cusps and kinks on cosmic strings
• How generic is cosmic string formation in SUSY GUTs
• The number of cosmic string loops
• Cosmological evolution of cosmic string loops
• Probing the gravitational wave background from cosmic strings with LISA
• The Production, Spectrum and Evolution of Cosmic Strings in Brane Inflation
• Stochastic gravitational wave background from smoothed cosmic string loops
• Power Spectra in Global Defect Theories of Cosmic Structure Formation
• Cosmic Strings and Superstrings
• Towards an Explicit Model of D-brane Inflation
• New limits on cosmic strings from gravitational wave observation
• Fractal Properties and Small-scale Structure of Cosmic String Networks
• Scaling of cosmic string loops
• Constraints on cosmic string tension imposed by the limit on the stochastic gravitational wave background from the European Pulsar Timing Array
• Constraints on cosmic strings using data from the first Advanced LIGO observing run
• CMB constraints on cosmic strings and superstrings
• The case against scaling defect models of cosmic structure formation
• Abelian Higgs Cosmic Strings: Small Scale Structure and Loops
• Inflation in Realistic D-Brane Models
• Scaling from gauge and scalar radiation in Abelian Higgs string networks
• Stochastic gravitational waves from cosmic string loops in scaling
• Seeking String Theory in the Cosmos
• Decay of Cosmic String Loops Due to Particle Radiation
• Constraints on cosmic strings from the LIGO-Virgo gravitational-wave detectors
• A detail study of defect models for cosmic structure formation
• Cosmic String Loops, Large and Small
• Particle emission and gravitational radiation from cosmic strings: observational constraints
• First LIGO search for gravitational wave bursts from cosmic (super)strings
• Cosmic-String-Seeded Structure Formation
• Cosmic string loop shapes
• Cosmic string loop production functions
• Observational constraints on light cosmic strings from photometry and pulsar timing
• Gravitational backreaction simulations of simple cosmic string loops
• GRAVITATIONAL RADIATION FROM REALISTIC COSMIC STRING LOOPS
• Energy-conservation constraints on cosmic string loop production and distribution functions
• Gravitational smoothing of kinks on cosmic string loops
• Shape of Cosmic String Loops
• Impact of the small-scale structure on the Stochastic Background of Gravitational Waves from cosmic strings
• Gravitational Wave Bursts from Cosmic String Cusps and Pseudocusps
• High Harmonic Configurations of Cosmic Strings: An Analysis of Self-Intersections
• Searches for Cosmic-String Gravitational-Wave Bursts in Mock LISA Data

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• Constraints on cosmic strings using data from the third Advanced LIGO-Virgo observing run
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