Dissecting the thermal Sunyaev-Zeldovich-gravitational lensing cross-correlation with hydrodynamical simulations

Understand

We use the cosmo-OWLS suite of cosmological hydrodynamical simulations, which includes different galactic feedback models, to predict the cross-correlation signal between weak gravitational lensing and the thermal Sunyaev-Zeldovich (tSZ) $y$-parameter.

• The predictions are compared to the recent detection reported by van Waerbeke and collaborators.
• The simulations reproduce the weak lensing-tSZ cross-correlation, $\xi_{y\kappa}(\theta)$, well.
• The uncertainty arising from different possible feedback models appears to be important on small scales only ($\theta \lesssim 10$ arcmin), while the amplitude of the correlation on all scales is sensitive to cosmological parameters that control the growth rate of structure (such as $\sigma_8$, $\Omega_m$ and $\Omega_b$).