Imprints of dark matter-massive neutrino interaction in upcoming post-reionization and galaxy surveys

We explore possible signatures of the interaction between dark matter (DM) and massive neutrinos during the post-reionization epoch. Using both Fisher matrix forecast analysis and Markov Chain Monte-Carlo (MCMC) simulation, we conduct a thorough investigation of the constraints and imprints of the scenario on the upcoming post-reionization and galaxy surveys. Our investigation focuses on two key parameters: the strength of the DM-massive neutrino interaction ($u$) and the total neutrino mass ($M_{\rm tot}$), on top of the usual 6 cosmological parameters. We utilize future 21-cm intensity mapping, galaxy clustering as well as cosmic shear observations in order to investigate the possible constraints of these parameters in the future observations: Square Kilometre Array (SKA1 and SKA2) and Euclid, taking both conservative and realistic approaches. All these missions show promise in constraining both the parameters $u$ and $M_{\rm tot}$ by few orders compared to the current constraints from Planck18 (SKA2 performing the best among them). Although we do not find much improvement in $H_0$ and $\sigma_8$ tensions from our forecast analysis, SKA2 constrains them better in conservative approach. We further perform a brief investigation of the prospects of some of the next generation Cosmic Microwave Background (CMB) missions in combinations with LSS experiments in improving the constraints. Our analysis reveals that both SKA2 and CMB-S4 + Euclid + SKA1 IM2 combination will put the strongest bounds on the model parameters.