The $\mathtt{WebSky}$ $[\mathrm{CII}]$ Forecasts and the search for primordial intermittent non-Gaussianity

Abstract

We present the $\mathtt{WebSky}$ $[\mathrm{CII}]$ line-intensity mock maps and forecast the capabilities of upcoming wide-field submillimeter-wave surveys of cosmological $[\mathrm{CII}]$ emission from the epoch of reionization (EoR). Using the $\mathtt{Peak}\mathtt{Patch}$ algorithm to generate light-cone dark matter (DM) halo catalogues and the $\mathtt{WebSky}$ framework to forward-model the cosmological $[\mathrm{CII}]$ signal, we construct tomographic mock surveys matched to the CCAT Observatory. We investigate both astrophysical models of $[\mathrm{CII}]$ emission from interstellar gas and the potential for the study of primordial intermittent non-Gaussianity (PING) as a science case for Stage 2 line intensity mapping (LIM) surveys. The $[\mathrm{CII}]$ voxel intensity distribution (VID) is used as a summary statistic in forecasts. Additional constraints on PING are derived from a relative entropy study of $\mathtt{Peak}\mathtt{Patch}$ halo mass functions. We show that upcoming LIM surveys will provide insights into the way we model cosmological line emission, and next-generation surveys can place competitive bounds on novel inflationary scenarios such as PING. The $\mathtt{WebSky}$ $[\mathrm{CII}]$ mocks and corresponding $\mathtt{Peak}\mathtt{Patch}$ halo catalogues are publicly available at https://uoft.me/webskycii .

45 pages, 14 figures, 1 table. Submitted to JCAP