English

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

Cosmology and Nongalactic Astrophysics 2025-10-22 v1

Abstract

We present the WebSky\mathtt{WebSky} [CII]\mathrm{[CII]} line-intensity mock maps and forecast the capabilities of upcoming wide-field submillimeter-wave surveys of cosmological [CII]\mathrm{[CII]} emission from the epoch of reionization (EoR). Using the Peak Patch\mathtt{Peak~Patch} algorithm to generate light-cone dark matter (DM) halo catalogues and the WebSky\mathtt{WebSky} framework to forward-model the cosmological [CII]\mathrm{[CII]} signal, we construct tomographic mock surveys matched to the CCAT Observatory. We investigate both astrophysical models of [CII]\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 [CII]\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 Peak Patch\mathtt{Peak~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 WebSky\mathtt{WebSky} [CII]\mathrm{[CII]} mocks and corresponding Peak Patch\mathtt{Peak~Patch} halo catalogues are publicly available at https://uoft.me/webskycii .

Keywords

Cite

@article{arxiv.2510.18312,
  title  = {The $\mathtt{WebSky}$ $\mathrm{[CII]}$ Forecasts and the search for primordial intermittent non-Gaussianity},
  author = {Nathan J. Carlson and J. Richard Bond and Dongwoo T. Chung and Patrick Horlaville and Thomas Morrison},
  journal= {arXiv preprint arXiv:2510.18312},
  year   = {2025}
}

Comments

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