The covariance of squeezed bispectrum configurations

We measure the halo bispectrum covariance in a large set of N-body simulations and compare it with theoretical expectations. find correlation among (even mildly) squeezed configurations. A similarly can be found between triangles long-wavelength power spectrum. This shows that diagonal Gaussian contribution fails to describe, even approximately, full these cases. our numerical estimate model includes, addition one, only non-Gaussian terms are for accounting modeling greatly improves agreement simulations. apply results simple Fisher matrix forecast, constraints on primordial non-Gaussianity degraded by factor $\sim 2$ when is assumed instead diagonal, approximation.