PIRSA:22120072

Cosmological parameters from BOSS and eBOSS data. Theoretical modeling of one-point probability distribution function for cosmological counts in cells.

Chudaykin, A. (2022). Cosmological parameters from BOSS and eBOSS data. Theoretical modeling of one-point probability distribution function for cosmological counts in cells.. Perimeter Institute. https://pirsa.org/22120072

Chudaykin, Anton. Cosmological parameters from BOSS and eBOSS data. Theoretical modeling of one-point probability distribution function for cosmological counts in cells.. Perimeter Institute, Dec. 19, 2022, https://pirsa.org/22120072 

          @misc{ pirsa_PIRSA:22120072,
            doi = {10.48660/22120072},
            url = {https://pirsa.org/22120072},
            author = {Chudaykin, Anton},
            keywords = {Cosmology},
            language = {en},
            title = {Cosmological parameters from BOSS and eBOSS data. Theoretical modeling of one-point probability distribution function for cosmological counts in cells.},
            publisher = {Perimeter Institute},
            year = {2022},
            month = {dec},
            note = {PIRSA:22120072 see, \url{https://pirsa.org}}
          }

Anton Chudaykin

University of Geneva (UNIGE)

Talk number
PIRSA:22120072
Collection
Talk Type
Subject
Abstract

In the first part of my talk, I present the effective-field theory (EFT)-based cosmological full-shape analysis of the anisotropic power spectrum of eBOSS quasars. We perform extensive tests of our pipeline on simulations, paying particular attention to the modeling of observational systematics. Assuming the minimal ΛCDM model, we find the Hubble constant H0 = (66.7 ± 3.2) km/s/Mpc, the matter density fraction Ωm = 0.32 ± 0.03, and the late-time mass fluctuation amplitude σ8 = 0.95 ± 0.08. These measurements are fully consistent with the Planck cosmic microwave background results. Our work paves the way for systematic full-shape analyses of quasar samples from future surveys like DESI. I also present the cosmological constraints from the full-shape BOSS+eBOSS data in various extensions of the ΛCDM model, such as massive neutrinos, dynamical dark energy and spatial curvature.

In the second part, I study the one-point probability distribution function (PDF) for matter density averaged over spherical cells. The leading part to the PDF is defined by the dynamics of the spherical collapse whereas the next-to-leading part comes from the integration over fluctuations around the saddle-point solution. The latter calculation receives sizable contributions from unphysical short modes and must be renormalized. We propose a new approach to renormalization by modeling the effective stress-energy tensor for short perturbations. The model contains three free parameters which can be related to the counterterms in the one-loop matter power spectrum and bispectrum. We demonstrate that this relation can be used to impose priors in fitting the model to the PDF data. We confront the model with the results of high-resolution N-body simulations and find excellent agreement for cell radii r≥10 Mpc/h at all redshifts up to z=0.

Zoom link:  https://pitp.zoom.us/j/92219627192?pwd=eGg4MDUrbGlrR2JqY0xyWHdwQ2lZZz09