The impact of braiding covariance and in-survey covariance on next-generation galaxy surveys

Understand

As galaxy surveys become more precise and push to smaller scales, the need for accurate covariances beyond the classical Gaussian formula becomes more acute.

• Here, I investigate the analytical implementation and impact of non-Gaussian covariance terms that I previously derived for galaxy clustering.
• Braiding covariance is such a class of terms and it gets contribution both from in-survey and super-survey modes.
• I present an approximation for braiding covariance which speeds up the numerical computation.