The impact of baryons on the sensitivity of dark energy measurements

Understand

Baryonic effects on large-scale structure, if not accounted for, can significantly bias dark energy constraints.

• As the detailed physics of the baryons is not yet well-understood, correcting for baryon effects introduces additional parameters which must be marginalized over, increasing the uncertainties on the inferred cosmological parameters.
• Forthcoming weak lensing surveys are aiming for percent-level precision on the dark energy equation of state, so the problem must be thoroughly examined.
• We use a halo model with analytic modifications which capture the impact of adiabatic contraction of baryons and feedback on the matter power spectrum, and generalize the Navarro-Frenk-White profile to account for a possible inner core.