Cosmological parameters and neutrino masses from the final <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>P</mml:mi><mml:mi>l</mml:mi><mml:mi>a</mml:mi><mml:mi>n</mml:mi><mml:mi>c</mml:mi><mml:mi>k</mml:mi></mml:math> and full-shape BOSS data

We present a joint analysis of the Planck cosmic microwave background (CMB) and Baryon Oscillation Spectroscopic Survey (BOSS) final data releases. A key novelty of our study is the use of a new full-shape (FS) likelihood for the redshift-space galaxy power spectrum of the BOSS data, based on an improved perturbation theory template. We show that the addition of the redshift-space galaxy clustering measurements breaks degeneracies present in the CMB data alone and tightens constraints on cosmological parameters. Assuming the minimal $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ cosmology with massive neutrinos, we find the following late-Universe parameters: the Hubble constant ${H}_{0}=67.9{5}_{\ensuremath{-}0.52}^{+0.66}\text{ }\text{ }\mathrm{km}\text{ }{\mathrm{s}}^{\ensuremath{-}1}\text{ }{\mathrm{Mpc}}^{\ensuremath{-}1}$, the matter density fraction ${\mathrm{\ensuremath{\Omega}}}_{m}=0.307{9}_{\ensuremath{-}0.0085}^{+0.0065}$, the mass fluctuation amplitude ${\ensuremath{\sigma}}_{8}=0.808{7}_{\ensuremath{-}0.0072}^{+0.012}$, and an upper limit on the sum of neutrino masses ${M}_{\mathrm{tot}}<0.16\text{ }\text{ }\mathrm{eV}$ (95% C.L.). This can be contrasted with the Planck-only measurements: ${H}_{0}=67.1{4}_{\ensuremath{-}0.72}^{+1.3}\text{ }\text{ }\mathrm{km}\text{ }{\mathrm{s}}^{\ensuremath{-}1}\text{ }{\mathrm{Mpc}}^{\ensuremath{-}1}$, ${\mathrm{\ensuremath{\Omega}}}_{m}=0.318{8}_{\ensuremath{-}0.016}^{+0.0091}$, ${\ensuremath{\sigma}}_{8}=0.805{3}_{\ensuremath{-}0.0091}^{+0.019}$, and ${M}_{\mathrm{tot}}<0.26\text{ }\text{ }\mathrm{eV}$ (95% C.L.). Our bound on the sum of neutrino masses relaxes once the hierarchy-dependent priors from the oscillation experiments are imposed. The addition of the new FS likelihood also constrains the effective number of extra relativistic degrees of freedom, ${N}_{\mathrm{eff}}=2.88\ifmmode\pm\else\textpm\fi{}0.17$. Our study shows that the current FS and the pure baryon acoustic oscillation data add a similar amount of information in combination with the Planck likelihood. We argue that this is just a coincidence given the BOSS volume and efficiency of the current reconstruction algorithms. In the era of future surveys FS will play a dominant role in cosmological parameter measurements.

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