Stochastic gravitational wave background generated by domain wall networks

• Tipo: Artigo em Revista Científica Internacional
• Data: 2024

Autores

Grüber, D (Autor) Outra; Sousa, L (Autor) Outra; Avelino, PP (Autor) FCUP

Revista

Título: Physical Review D: Particles and fields

Vol. 110

ISSN: 0556-2821

Editora: American Physical Society

Indexação

ISI Web of Knowledge - 0 Citações

Scopus - 0 Citações

Outras Informações

ID Authenticus: P-010-YRT

DOI: 10.1103/physrevd.110.023505

Abstract (EN): In this work we study the power spectrum of the stochastic gravitational wave background produced by standard and biased domain wall networks, using the velocity-dependent one-scale model to compute the cosmological evolution of their characteristic scale and root-mean-squared velocity. We consider a standard radiation & thorn; Lambda CDM background and assume that a constant fraction of the energy of collapsing domain walls is emitted in the form of gravitational waves. We show that, in an expanding background, the total energy density in gravitational radiation decreases with cosmic time (after a short initial period of quick growth). We also propose a two parameter model for the scale-dependence of the frequency distribution of the gravitational waves emitted by collapsing domain walls. We determine the corresponding power spectrum of the stochastic gravitational wave background generated by domain walls, showing that it is a monotonic decreasing function of the frequency for frequencies larger than that of the peak generated by the walls that have decayed most recently. We also develop an analytical approximation to this spectrum, assuming perfect linear scaling during both the radiation and matter eras, in order to characterize the dependence of the amplitude, peak frequency and slope of the power spectrum on the model parameters.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 16