Results
DESI measures the growth and expansion history of the universe two ways, from two very different tracers — and the collaboration organizes the work accordingly.
Galaxies and quasars are counted as discrete objects, and their clustering is measured out to redshift about 2. The Lyman-α forest instead measures absorption by intergalactic hydrogen along the line of sight to distant quasars, reaching redshifts beyond 2 where galaxies are too faint to survey in bulk.
Each tracer is analyzed both ways: for the baryon acoustic oscillation feature alone — a standard ruler giving distances — and for the full shape of the correlation functions, which adds the Alcock-Paczyński effect and the growth rate of structure. A third effort, cosmological parameter estimation, combines all of it with the CMB and supernovae to constrain dark energy and the neutrino masses. The pages below follow that division, as DESI's own working groups do.
BAO
The standard ruler, measured from galaxies and quasars out to z ≈ 2.1 and from the Lyman-α forest at z ≈ 2.3.
Full Shape
Beyond the BAO peak: broadband clustering, the Alcock-Paczyński effect and the growth rate of structure.
Cosmological Parameter Estimation
The headline results — dark energy, neutrino mass and extended models, from every probe combined.
Lyman-α
The forest program: how a measurement is built, the pipeline reference set, and the 1D power spectrum.
Beyond cosmology
DESI's spectra support work well outside the cosmology program — Milky Way dynamics and mass, stellar populations, quasar physics and transients among them. Results in those areas will be added here as the group takes them up.