Oral Presentation

A Unified Tracer Analysis of DESI DR2 BAO

Author(s): Nick Sanders (Ohio University)

Presenter: Nick Sanders (Ohio University)

DESI traces the matter distribution of the universe via observations of multiple distinct galaxy populations (tracers). Tracers have significant overlap in redshift, meaning they trace the same underlying matter distribution and are in principle not independent. We extend a method for naturally accounting for this cross-tracer information to all overlapping tracers in DESI DR2 by combining all tracers into a single catalog. In addition to including cross information, the unified tracer also allows for padding in redshift during reconstruction in order to avoid anomalous displacements at the boundaries, as well as a smooth displacement field across boundaries of individual tracers. We also use this unified tracer to perform cosmology inference with a different redshift binning than would be allowed treating each tracer separately.