Radio–optical galaxy shape correlations in the COSMOS field

We investigate the correlations in galaxy shapes between optical and radio wavelengths using archival observations of the COSMOS field. Cross-correlation studies between different wavebands will become increasingly important for precision cosmology as future large surveys may be dominated by systematic rather than statistical errors. In the case of weak lensing, galaxy shapes must be measured to extraordinary accuracy (shear systematics of $ 0.212\pi$ radians (or $38.2^{\circ}$) at a $95\%$ confidence level.