Halo squeezed-limit bispectrum with primordial non-Gaussianity: A power spectrum response approach

摘要: Modeling the nonlinearity of halo bispectrum remains a major challenge in modern cosmology, particular for ongoing and upcoming large-scale structure observations that are performed to study inflationary physics. The "power spectrum response" offers solution so-called squeezed limit, which one wavenumber is much smaller than other two. As first step, we demonstrate squeezed-limit computed from second-order standard perturbation theory agrees precisely with responses linear power density potential fluctuations. Since arbitrarily small scales can straightforwardly be obtained by separate universe simulations, response approach provides novel powerful technique modeling nonlinear bispectrum.