On the IR-Resummation in the EFTofLSS

Understand

We propose a simplification for the IR-resummation scheme of Senatore and Zaldarriaga, and also include its next-to-leading order corrections coming from the tree-level three-point function of the long displacement field.

• First we show that the new simplified formula shares the same properties of the resummation of Senatore and Zaldarriaga.
• In Fourier space, the IR-resummed power spectrum has no residual wiggles and the two-loop calculation matches the non-linear power spectrum of the Dark Sky simulation at $z=0$ up to $k\simeq0.34\,h\,\text{Mpc}^{-1}$ within cosmic variance.
• Then, we find that the additional subleading terms (although parametrically infrared-enhanced) modify the leading-order IR-resummed correlation function only in a marginal way, implying that the IR-resummation scheme can robustly predict the shape of the BAO peak.