Baryon oscillations in galaxy and matter power-spectrum covariance matrices

Understand

We investigate large-amplitude baryon acoustic oscillations (BAO's) in off-diagonal entries of cosmological power-spectrum covariance matrices.

• These covariance-matrix BAO's describe the increased attenuation of power-spectrum BAO's caused by upward fluctuations in large-scale power.
• We derive an analytic approximation to covariance-matrix entries in the BAO regime, and check the analytical predictions using N-body simulations.
• These BAO's look much stronger than the BAO's in the power spectrum, but seem detectable only at about a one-sigma level in gigaparsec-scale galaxy surveys.