J-PAS: Forecasts for dark matter - dark energy elastic couplings

TL;DR

This paper investigates a cosmological model with dark matter-dark energy coupling affecting momentum transfer, confirming previous evidence of such coupling and forecasting future survey capabilities to detect it with high significance.

Contribution

The study provides the first forecast for J-PAS data on dark matter-dark energy coupling, demonstrating its potential to detect or constrain the interaction with high confidence.

Findings

Current data favor a non-zero coupling at over 3σ, mainly driven by Sunyaev-Zeldovich observations.

Future J-PAS clustering measurements can detect the coupling at more than 10σ significance.

Weak lensing measurements do not significantly improve constraints on the coupling parameter.

Abstract

We consider a cosmological model where dark matter and dark energy feature a coupling that only affects their momentum transfer in the corresponding Euler equations. We perform a fit to cosmological observables and confirm previous findings within these scenarios that favour the presence of a coupling at more than $3\sigma$. This improvement is driven by the Sunyaev-Zeldovich data. We subsequently perform a forecast for future J-PAS data and find that clustering measurements will permit to clearly discern the presence of an interaction within a few percent level with the uncoupled case at more than $10\sigma$ when the complete survey, covering $8500$ sq. deg., is considered. We found that the inclusion of weak lensing measurements will not help to further constrain the coupling parameter. For completeness, we compare to forecasts for DESI and Euclid, which provide similar discriminating power.