Radiation from Global Topological Strings using Adaptive Mesh Refinement: Methodology and Massless Modes

Abstract

We implement adaptive mesh refinement (AMR) simulations of global topological strings using the public numerical relativity code, GRChombo. We perform a quantitative investigation of the dynamics of single sinusoidally displaced string configurations, studying a wide range of string energy densities $\mu \propto \ln \lambda$, defined by the string width parameter $\lambda$ over two orders of magnitude. We investigate the resulting massless (Goldstone boson or axion) radiation signals, using quantitative diagnostic tools to determine the eigenmode decomposition. Given analytic radiation predictions, we compare the oscillating string trajectory with a backreaction model accounting for radiation energy losses, finding excellent agreement. We establish that backreaction decay is accurately characterised by the inverse square of the amplitude being proportional to the inverse tension $\mu$ for $3\lesssim \lambda \lesssim 100$. We conclude that analytic radiation modelling in the thin-string (Nambu-Goto) limit provides the appropriate cosmological limit for global strings. We contextualise these results with respect to axions and gravitational waves produced by cosmic string networks.

arXiv comment25 pages, 28 figures, version published in PRD including convergence tests

References in corpus (39)

• Axion Cosmology
• On the Numerical Integration of Einstein's Field Equations
• The Einstein Toolkit: A Community Computational Infrastructure for Relativistic Astrophysics
• The number of cosmic string loops
• Axion Cosmology Revisited
• Axions from Strings: the Attractive Solution
• Large parallel cosmic string simulations: New results on loop production
• More Axions from Strings
• Production of dark matter axions from collapse of string-wall systems
• Turduckening black holes: an analytical and computational study
• Numerical simulations of string networks in the Abelian-Higgs model
• Binary black-hole evolutions of excision and puncture data
• Constraints on cosmic strings using data from the first Advanced LIGO observing run
• On the Evolution of Abelian-Higgs String Networks
• Axion String Constraints
• Global String Radiation
• Evolution of Axionic Strings and Spectrum of Axions Radiated from Them
• GRChombo : Numerical Relativity with Adaptive Mesh Refinement
• Black hole formation from axion stars
• Robustness of Inflation to Inhomogeneous Initial Conditions
• End Point of Black Ring Instabilities and the Weak Cosmic Censorship Conjecture
• The scaling density of axion strings
• Long-term dynamics of cosmological axion strings
• End Point of the Ultraspinning Instability and Violation of Cosmic Censorship
• Gravitational Wave Emission from Collisions of Compact Scalar Solitons
• How to simulate global cosmic strings with large string tension
• Numerical relativity for D dimensional axially symmetric space-times: formalism and code tests
• Cosmic String Loop Collapse in Full General Relativity
• Robustness of Inflation to Large Tensor Perturbations
• Binary black holes on a budget: Simulations using workstations
• Axion star collisions with black holes and neutron stars in full 3D numerical relativity
• Formation of Relativistic Axion Stars
• Numerical evolution of multiple black holes with accurate initial data
• Growth of accretion driven scalar hair around Kerr black holes
• Radiative Backreaction on Global Strings
• Inhomogeneous initial conditions for inflation: A wibbly-wobbly timey-wimey path to salvation
• Black hole interference patterns in flavour oscillations
• Axion dark matter and the Lattice
• Critical Phenomena in Non-spherically Symmetric Scalar Bubble Collapse

Cited by in corpus (16)

• More Axions from Strings
• Dark Matter from Axion Strings with Adaptive Mesh Refinement
• The Science of the Einstein Telescope
• Spectrum of global string networks and the axion dark matter mass
• Lessons for adaptive mesh refinement in numerical relativity
• Global cosmic string networks as a function of tension
• Gravitational Wave Emission from a Cosmic String Loop, I: Global Case
• Generalised velocity-dependent one-scale model for current-carrying strings
• Radiation from Global Topological Strings using Adaptive Mesh Refinement: Massive Modes
• Aspects of Axions and ALPs Phenomenology
• Where is the ringdown? Reconstructing quasinormal modes from dispersive waves
• Parametric Resonances in Axionic Cosmic Strings
• Cosmic Microwave Background Signatures from Current-carrying Cosmic Strings
• Bunch-Davies initial conditions and non-perturbative inflationary dynamics in Numerical Relativity
• Spectrum of radiation from global strings and the relic axion density
• Physics beyond the Standard Model with the DSA-2000