Stochastic gravitational-wave background from metastable cosmic strings

Abstract

A metastable cosmic-string network is a generic consequence of many grand unified theories (GUTs) when combined with cosmic inflation. Metastable cosmic strings are not topologically stable, but decay on cosmic time scales due to pair production of GUT monopoles. This leads to a network consisting of metastable long strings on superhorizon scales as well as of string loops and segments on subhorizon scales. We compute for the first time the complete stochastic gravitational-wave background (SGWB) arising from all these network constituents, including several technical improvements to both the derivation of the loop and segment contributions. We find that the gravitational waves emitted by string loops provide the main contribution to the gravitational-wave spectrum in the relevant parameter space. The resulting spectrum is consistent with the tentative signal observed by the NANOGrav and Parkes pulsar timing collaborations for a string tension of Gμ~ 10^-11...-7 and has ample discovery space for ground- and space-based detectors. For GUT-scale string tensions, Gμ~ 10^-8...-7, metastable strings predict a SGWB in the LIGO-Virgo-KAGRA band that could be discovered in the near future.

31 pages, 6 figures. v2: signal recently reported by the Parkes Pulsar Timing Array (PPTA) collaboration [2107.12112] added to Figs. 2 to 4

References in corpus (8)

• Laser Interferometer Space Antenna
• On the evidence for a common-spectrum process in the search for the nanohertz gravitational-wave background with the Parkes Pulsar Timing Array
• Stochastic gravitational wave background from smoothed cosmic string loops
• Cosmic string loop distribution on all length scales and at any redshift
• Massive black hole binary systems and the NANOGrav 12.5 year results
• Spontaneous B-L Breaking as the Origin of the Hot Early Universe
• The spontaneous breaking of a metastable string
• Primordial Monopoles and Strings, Inflation, and Gravity Waves

Cited by in corpus (67)

• The NANOGrav 15-year Data Set: Search for Signals from New Physics
• The recent gravitational wave observation by pulsar timing arrays and primordial black holes: the importance of non-gaussianities
• Inflationary interpretation of the stochastic gravitational wave background signal detected by pulsar timing array experiments
• Primordial gravitational waves from NANOGrav: a broken power-law approach
• Cosmological Background Interpretation of Pulsar Timing Array Data
• Detection of Early-Universe Gravitational Wave Signatures and Fundamental Physics
• The Science of the Einstein Telescope
• Gravitational Waves from SMBH Binaries in Light of the NANOGrav 15-Year Data
• Leptogenesis triggered by a first-order phase transition
• Scalar induced gravity waves from ultra slow-roll Galileon inflation
• Ultrahigh frequency primordial gravitational waves beyond the kHz: The case of cosmic strings
• Cosmic strings from pure Yang-Mills theory
• Sneutrino Tribrid Inflation, Metastable Cosmic Strings and Gravitational Waves
• Primordial non-Gaussianity as a saviour for PBH overproduction in SIGWs generated by Pulsar Timing Arrays for Galileon inflation
• Realisation of the ultra-slow roll phase in Galileon inflation and PBH overproduction
• Constraining gravitational wave propagation using pulsar timing array correlations
• Composite Topological Structures in SO(10)
• Inflation, superheavy metastable strings and gravitational waves in non-supersymmetric flipped SU(5)
• Gravitational Waves from Quasi-stable Strings
• Evading no-go for PBH formation and production of SIGWs using Multiple Sharp Transitions in EFT of single field inflation
• $\mu$-hybrid Inflation, Gravitino Dark Matter and Stochastic Gravitational Wave Background from Cosmic Strings
• Hunting the stochastic gravitational wave background in pulsar timing array cross correlations through theoretical uncertainty
• Monopoles, Strings and Gravitational Waves in Non-minimal Inflation
• Large fluctuations and Primordial Black Holes
• Cosmic F- and D-strings from pure Yang-Mills theory
• Testing Realistic $SO(10)$ SUSY GUTs with Proton Decay and Gravitational Waves
• Probing Stochastic Gravitational Wave Background from $SU(5)\times U(1{)}_{\chi }$ Strings in Light of NANOGrav 15-Year Data
• Gravitational wave emission from metastable current-carrying strings in $E_6$
• Constraining the Cosmic Strings Gravitational Wave Spectra in No Scale Inflation with Viable Gravitino Dark matter and Non Thermal Leptogenesis
• Probing Miracle-less WIMP Dark Matter via Gravitational Waves Spectral Shapes
• Obviating PBH overproduction for SIGWs generated by Pulsar Timing Arrays in loop corrected EFT of bounce
• A Predictive $SO(10)$ Model
• Flipped SU(5): unification, proton decay, fermion masses and gravitational waves
• Improving the detection sensitivity to primordial stochastic gravitational waves with reduced astrophysical foregrounds
• Revisiting Metastable Cosmic String Breaking
• Charting the Nanohertz Gravitational Wave Sky with Pulsar Timing Arrays
• Imprint of PBH domination on gravitational waves generated by cosmic strings
• Quantum tunneling in the early universe: Stable magnetic monopoles from metastable cosmic strings
• Untangling PBH overproduction in $w$-SIGWs generated by Pulsar Timing Arrays for MST-EFT of single field inflation
• Gravitational waves from low-scale cosmic strings
• Topological structures, dark matter and gravitational waves in $E_6$
• Superheavy Metastable Strings in SO(10)
• Kinetic Mixing, Proton Decay and Gravitational Waves in SO(10)
• Negative non-Gaussianity as a salvager for PBHs with PTAs in bounce
• C-parity, magnetic monopoles and higher frequency gravitational waves
• Toward a test of Gaussianity of a gravitational wave background
• Gravitational Waves of GUT Phase Transition during Inflation
• Future targets for light gauge bosons from cosmic strings
• Tracking Down the Route to the SM with Inflation and Gravitational Waves
• Untargeted Bayesian search of anisotropic gravitational-wave backgrounds through the analytical marginalization of the posterior
• Gravitational Waves from Metastable Cosmic Strings in Supersymmetric New Inflation Model
• Improving the detection sensitivity to primordial stochastic gravitational waves with reduced astrophysical foregrounds. II. Subthreshold binary neutron stars
• Crescendo Beyond the Horizon: More Gravitational Waves from Domain Walls Bounded by Inflated Cosmic Strings
• Non-Abelian Domain Walls and Gravitational Waves
• E- & T-Model Hybrid Inflation
• Supersymmetric hybrid inflation and current-carrying metastable cosmic strings in $SU(4{)}_c\times SU(2{)}_L\times U(1{)}_R$
• Inflation, Proton Decay and Gravitational Waves from Metastable Strings in $SU(4{)}_C\times SU(2{)}_L\times U(1{)}_R$ Model
• Implications of pulsar timing arrays for Gauss-Bonnet Inflation
• Magnetic monopoles and high frequency gravitational waves from quasi-stable strings
• A New Census of the Universe's Entropy
• Gravitational wave signal from primordial magnetic fields in the Pulsar Timing Array frequency band
• Testing No slip model with pulsar timing arrays: NANOGrav and IPTA
• Gravitational Wave Driven Inspirals of Binaries Connected by Cosmic Strings
• Time-dependent deflection reconstruction: new technique to search for gravitational waves with the cosmic microwave background
• Superconducting Strings in $E_6$
• Searching Stochastic Gravitational Wave Background Landscape Across Frequency Bands
• Metastable cosmic strings are broken at the start