Astrometric effects of gravitational wave backgrounds with non-Einsteinian polarizations
Physical Review D - Particles, Fields, Gravitation and Cosmology
American Physical Society
MetadataShow full item record
Mihaylov, D., Moore, C., Gair, J., Lasenby, A., & Gilmore, G. (2018). Astrometric effects of gravitational wave backgrounds with non-Einsteinian polarizations. Physical Review D - Particles, Fields, Gravitation and Cosmology, 97 (124058)https://doi.org/10.1103/PhysRevD.97.124058
The Gaia mission offers a new opportunity to search for the low-frequency gravitational wave background using astrometric measurements. In this paper, the astrometric effect of gravitational waves is reviewed, with a particular focus on the effect of non-Einsteinian gravitational wave polarizations. A stochastic gravitational wave background generates a correlated vector field of astrometric deflections on the sky. A convenient decomposition for the correlation matrix is introduced, enabling it to be calculated for all possible gravitational wave polarizations and compared to the redshift correlations from the pulsar-timing literature; in the case of a general relativity background of transverse traceless gravitational waves, this also allows us to identify an astrometric analog of the famous Hellings-Downs curve. Finally, the cross correlation between the redshift and astrometric signal is also calculated; this may form the basis for future joint pulsar-timing and astrometry searches for arbitrarily polarized gravitational wave backgrounds.
D. M. is funded by the STFC. C. M. acknowledges financial support provided under the European Union’s H2020 ERC Consolidator Grant “Matter and strong-field gravity: New frontiers in Einsteins theory” grant agreement no. MaGRaTh646597. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 690904 and C. M. would like to acknowledge networking support by the COST Action CA16104.
ECH2020 EUROPEAN RESEARCH COUNCIL (ERC) (646597)
European Commission Horizon 2020 (H2020) Marie Sk?odowska-Curie actions (690904)
External DOI: https://doi.org/10.1103/PhysRevD.97.124058
This record's URL: https://www.repository.cam.ac.uk/handle/1810/283558