Kavli Affiliate: Jia Liu
| First 5 Authors: Adrian E. Bayer, Jia Liu, Ryo Terasawa, Alexandre Barreira, Yici Zhong
| Summary:
We study the effect of super-sample covariance (SSC) on the power spectrum
and higher-order statistics: bispectrum, halo mass function, and void size
function. We also investigate the effect of SSC on the cross covariance between
the statistics. We consider both the matter and halo fields. Higher-order
statistics of the large-scale structure contain additional cosmological
information beyond the power spectrum and are a powerful tool to constrain
cosmology. They are a promising probe for ongoing and upcoming high precision
cosmological surveys such as DESI, PFS, Rubin Observatory LSST, Euclid,
SPHEREx, SKA, and Roman Space Telescope. Cosmological simulations used in
modeling and validating these statistics often have sizes that are much smaller
than the observed Universe. Density fluctuations on scales larger than the
simulation box, known as super-sample modes, are not captured by the
simulations and in turn can lead to inaccuracies in the covariance matrix. We
compare the covariance measured using simulation boxes containing super-sample
modes to those without. We also compare with the Separate Universe approach. We
find that while the power spectrum, bispectrum and halo mass function show
significant scale- or mass-dependent SSC, the void size function shows
relatively small SSC. We also find significant SSC contributions to the cross
covariances between the different statistics, implying that future
joint-analyses will need to carefully take into consideration the effect of
SSC. To enable further study of SSC, our simulations have been made publicly
available at https://github.com/HalfDomeSims/ssc.
| Search Query: ArXiv Query: search_query=au:”Jia Liu”&id_list=&start=0&max_results=3