Coupling parsec and gigaparsec scales: Primordial non-Gaussianity with multitracer intensity mapping

Primordial non-Gaussianity (PNG) is a key probe of the origins primordial fluctuations in early universe. It has been shown that multitracer measurements large-scale structure can produce high-precision PNG. Future line intensity mapping surveys are well suited to these owing their ability rapidly survey large volumes and access scales at which PNG becomes important. In this paper, we explore for first time how with depend on sub-galactic scale physics drives emission. We consider an example cross-correlation between CO maps, quantify impact varying astrophysical model ${f}_{\mathrm{NL}}$ measurements. find nontrivial coupling horizon-scale molecular cloud-scale interstellar medium have order unity effects constraints near-future experimental sensitivities. discuss noise level design. further shot noise, effect nearly unique measurements, play important role multi-tracer analyses should not be neglected.