Predicting the formation of stars, black holes, and gravitational-wave signals with young galaxy clusters

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K13911
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 15010:Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics
• Research Institution: The University of Tokyo
• Principal Investigator: Ata Metin 東京大学, カブリ数物連携宇宙研究機構, 客員准科学研究員 (60836229)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: Large-scale structure / Gravitational waves

Outline of Final Research Achievements

I initially designed this project to utilize high redshift density reconstructions that I was working on at the moment. The idea of using density maps located in the era of maximum star formation is motivated as merging stellar remnants such as neutron stars and black holes, are the astrophysical sources of gravitational waves.
I was able to accomplish to close the gap of observational studies and cosmological simulations, however, I had to restructure the project in a general way. The initial idea to resolve stellar size that lie in the LIGA-VIRGO-KARGA frequency band turned out to be unfeasible. Therefore, I switched the focus to the Stochastic gravitational wave background in the nano-hertz band that is sourced by merging super-massive blackholes. These objects can very accurately be resolved in large-scale cosmological simulations, which makes this project an ideal use-case for the new density maps that I am creating now.

Free Research Field

Cosmology

Academic Significance and Societal Importance of the Research Achievements

The confirmation of the stochastic gravitational wave background by the NANOGrav collaboration last year boosted the significance of this project massively, especially our unique ability to estimate the anisotropies in the stochastic background.