We present a model for the squeezed dark matter bispectrum, where the short modes are deep in the non-linear regime. We exploit the consistency relations for large-scale structures combined with a response function approach to write the squeezed bispectrum in terms of a few unknown functions of the short modes. We provide an ansatz for a fitting function for these response functions, checking that the resulting model is reliable when compared to the one-loop squeezed bispectrum. We then test the model against measured bispectra from numerical simulations for short modes ranging between k∼0.1h/Mpc, and k∼0.7h/Mpc at redshift z=0. To evaluate the goodness of the fit of our model we implement a non-Gaussian covariance and find agreement within 1-σ standard deviation of the simulated data.
@article{arxiv.2212.11940,
title = {A Model for the Squeezed Bispectrum in the Non-Linear Regime},
author = {Matteo Biagetti and Juan Calles and Lina Castiblanco and Katherine González and Jorge Noreña},
journal= {arXiv preprint arXiv:2212.11940},
year = {2023}
}
Comments
19 pages, 5 figures; v2 added references, corrected minor typos, prepared for submission to JCAP