2022/01/11 by Sebastian Golat, Carlo Contaldi, Carlo R. Contaldi
Earth and Planetary Sciences · Physics and Astronomy · #Anisotropy #Classical mechanics #Formalism (music) #Geophysics and Gravity Measurements #Gravitation #Gravitational wave #Observable #Physics #Pulsars and Gravitational Waves Research #Quantum mechanics #Spherical harmonics #Statistical physics #Stellar, planetary, and galactic studies #Theoretical physics #astro-ph.CO #gr-qc
paper · pdf · doi:10.1103/physrevd.105.063502
15 pages, 7 figures, 4 tables
arxiv created 2022/01/11 · openalex publication_date 2022/03/01 · arxiv updated 2022/03/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We introduce a unified formalism to describe both timing and astrometric perturbations induced on astrophysical point sources by gravitational waves using a complex spin field on the sphere. This allows the use of spin-weighted spherical harmonics to analyse "astrochronometric" observables. This approach simplifies the interpretation and simulation of anisotropies induced in the observables by gravitational waves. It also allows a simplified derivation of angular cross-spectra of the observables and their relationship with generalised Hellings-Downs correlation functions. The spin-weighted formalism also allows an explicit connection between correlation components and the spin of gravitational wave polarisations and any presence of chirality. We also calculate expected signal-to-noise ratios for observables to compare the utility of timing and deflection observables.