Primordial black hole archaeology with gravitational waves from cosmic strings

Ghoshal, Anish; Gouttenoire, Yann; Heurtier, Lucien; Simakachorn, Peera

Abstract

Light primordial black holes (PBHs) with masses smaller than 109 g (10−24M⊙) evaporate before the onset of Big-Bang nucleosynthesis, rendering their detection rather challenging. If efficiently produced, they may have dominated the universe energy density. We study how such an early matter-dominated era can be probed successfully using gravitational waves (GW) emitted by local and global cosmic strings. While previous studies showed that a matter era generates a single-step suppression of the GW spectrum, we instead find a double-step suppression for local-string GW whose spectral shape provides information on the duration of the matter era. The presence of the two steps in the GW spectrum originates from GW being produced through two events separated in time: loop formation and loop decay, taking place either before or after the matter era. The second step — called the knee — is a novel feature which is universal to any early matter-dominated era and is not only specific to PBHs. Detecting GWs from cosmic strings with LISA, ET, or BBO would set constraints on PBHs with masses between 106 and 109 g for local strings with tension Gμ = 10−11, and PBHs masses between 104 and 109 g for global strings with symmetry-breaking scale η = 1015 GeV. Effects from the spin of PBHs are discussed.

Citation

Ghoshal, A., Gouttenoire, Y., Heurtier, L., & Simakachorn, P. (2023). Primordial black hole archaeology with gravitational waves from cosmic strings. Journal of High Energy Physics, 2023(8), Article 196. https://doi.org/10.1007/jhep08%282023%29196

• Journal Article Type: Article
• Acceptance Date: Aug 18, 2023
• Online Publication Date: Aug 29, 2023
• Publication Date: Aug 29, 2023
• Deposit Date: Jan 8, 2024
• Publicly Available Date: Jan 8, 2024
• Journal: Journal of High Energy Physics
• Print ISSN: 1126-6708
• Electronic ISSN: 1029-8479
• Publisher: Scuola Internazionale Superiore di Studi Avanzati (SISSA)
• Peer Reviewed: Peer Reviewed
• Volume: 2023
• Issue: 8
• Article Number: 196
• DOI: https://doi.org/10.1007/jhep08%282023%29196
• Keywords: Cosmology of Theories BSM, Specific BSM Phenomenology, Phase Transitions in the Early Universe, Early Universe Particle Physics
• Public URL: https://durham-repository.worktribe.com/output/1881329