Spectrum of gravitational waves from long-lasting primordial sources
Fuente:
arXiv
Saved in:
| Main Author: | |
|---|---|
| Format: | Preprint |
| Published: |
2023
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866911781793824768 |
|---|---|
| author | Ramazanov, Sabir |
| author_facet | Ramazanov, Sabir |
| contents | We discuss long-lasting gravitational wave sources arising and operating during radiation-dominated stage. Under a set of assumptions, we establish the correspondence between cosmological evolution of a source and the resulting gravitational wave spectrum. Namely, for the source energy density $ρ_s$ falling as a power law characterized by the exponent $β$, i.e., $ρ_s \propto 1/a^β$, where $a$ is the Universe scale factor, the spectrum takes the form $Ω_{gw} \propto f^{2β-8}$ in certain ranges of values of constant $β$ and frequencies $f$. In particular, matching to the best fit power law shape of stochastic gravitational wave background discovered recently by Pulsar Timing Array collaborations, one identifies $β\approx 5$. We demonstrate the correspondence with concrete examples of long-lasting sources: domain walls and cosmic strings. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2310_19148 |
| institution | arXiv |
| publishDate | 2023 |
| record_format | arxiv |
| spellingShingle | Spectrum of gravitational waves from long-lasting primordial sources Ramazanov, Sabir General Relativity and Quantum Cosmology Cosmology and Nongalactic Astrophysics High Energy Physics - Phenomenology High Energy Physics - Theory We discuss long-lasting gravitational wave sources arising and operating during radiation-dominated stage. Under a set of assumptions, we establish the correspondence between cosmological evolution of a source and the resulting gravitational wave spectrum. Namely, for the source energy density $ρ_s$ falling as a power law characterized by the exponent $β$, i.e., $ρ_s \propto 1/a^β$, where $a$ is the Universe scale factor, the spectrum takes the form $Ω_{gw} \propto f^{2β-8}$ in certain ranges of values of constant $β$ and frequencies $f$. In particular, matching to the best fit power law shape of stochastic gravitational wave background discovered recently by Pulsar Timing Array collaborations, one identifies $β\approx 5$. We demonstrate the correspondence with concrete examples of long-lasting sources: domain walls and cosmic strings. |
| title | Spectrum of gravitational waves from long-lasting primordial sources |
| topic | General Relativity and Quantum Cosmology Cosmology and Nongalactic Astrophysics High Energy Physics - Phenomenology High Energy Physics - Theory |
| url | https://arxiv.org/abs/2310.19148 |