A brief review on cosmological analysis of galaxy surveys with multiple tracers

TL;DR

This review discusses the multi-tracer method in galaxy surveys, which aims to reduce cosmic variance by using multiple biased tracers, enhancing the precision of cosmological measurements.

Contribution

It summarizes the concept, data analysis steps, and provides practical examples from major galaxy surveys, highlighting the method's application in cosmology.

Findings

Multi-tracer approach can mitigate cosmic variance.

Worked examples demonstrate practical implementation.

Enhanced measurement precision in galaxy surveys.

Abstract

Galaxy redshift surveys are one of the key probes in modern cosmology. In the data analysis of galaxy surveys, the precision of the statistical measurement is primarily limited by the cosmic variance on large scales. Fortunately, this limitation can in principle be evaded by observing multiple types of biased tracers. In this brief review, we present the idea of the multi-tracer method, outline key steps in the data analysis, and show several worked examples based on the GAMA, BOSS and eBOSS galaxy surveys.