2026/01/22 by Mikhail M. Ivanov, James M. Sullivan, Roger de Belsunce +4 · 2 citations
#astro-ph.CO #hep-ex #hep-ph #hep-th
We present cosmological parameter measurements from the full combination of DESI DR1 galaxy clustering data, described with large-scale structure effective field theory. By incorporating photometric galaxies and CMB lensing cross-correlations, and extending the bispectrum likelihood to smaller scales with a consistent one-loop computation, we achieve substantial gains in constraining power. Combined with the latest DESI baryon acoustic oscillation (BAO) data and cosmic microwave background (CMB) priors on the spectral tilt and baryon density, we find, in ΛCDM, H0=69.08± 0.37~km s-1Mpc-1, Ωm=0.2974± 0.0050, and σ8 = 0.838± 0.017 (S8 = σ8√(Ωm/0.3) =0.834± 0.018). Adding the Pantheon+ supernovae (SNe), we find a 2.2σ preference for the w0wa dynamical dark energy model from low-redshift data alone, rising to 2.7σ when exchanging the SNe for Planck CMB data. Combining the full-shape, BAO, CMB, and SNe likelihoods improves the dark energy figure-of-merit by 15% and bounds the neutrino mass sum to Mν<0.049 eV (ΛCDM) and Mν<0.077 eV (w0waCDM) at 95% CL. This is the strongest w0waCDM bound to date, 37% tighter than from the background expansion data alone. The preference for the normal neutrino mass ordering thus holds regardless of the background model: the inverted hierarchy is disfavored at ≈ 3.5σ in ΛCDM and ≈ 2.4σ in w0waCDM, with the latter constraint free of the geometric tension between CMB and BAO that is known to sharpen the ΛCDM bound.