Year: 2025
Type: article
Abstract: We propose a novel statistical method to measure cosmic birefringence and demonstrate its power in probing parity violation due to axions. Exploiting an empirical correlation between the integrated radio polarization direction of a spiral galaxy and its apparent shape, we devise an unbiased minimum-variance estimator for the rotation angle, which should achieve an uncertainty of 5°-15° per galaxy. Large galaxy samples from the forthcoming SKA continuum surveys, together with optical shape catalogs, promise a comparable or even lower noise power spectrum for the rotation angle than in the CMB Stage-IV (CMB-S4) experiment, with different systematics.
Source: Physical Review Letters
Institutions: Perimeter Institute, Lawrence Berkeley National Laboratory
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: U.S. Department of Energy, Alfred P. Sloan Foundation, Innovation, Science and Economic Development Canada, Government of Canada, Ontario Ministry of Economic Development and Innovation, Ministero dello Sviluppo Economico, Institut Périmètre de physique théorique, Office of Science, High Energy Physics, Lawrence Berkeley National Laboratory
OpenAlex ID: W4409660849