Young and Intermediate-age Distance Indicators

TL;DR

This paper reviews young and intermediate-age standard candles like Cepheids, Mira variables, and Red Clump stars, discussing their properties, calibration challenges, and recent advances in their use for measuring cosmic distances.

Contribution

It provides a comprehensive overview of the fundamental properties and recent developments in applying young and intermediate-age standard candles for distance measurement.

Findings

Analysis of calibration dependencies on chemical composition and age

Discussion of contamination and systematic uncertainties

Summary of recent methodological advancements

Abstract

Distance measurements beyond geometrical and semi-geometrical methods, rely mainly on standard candles. As the name suggests, these objects have known luminosities by virtue of their intrinsic proprieties and play a major role in our understanding of modern cosmology. The main caveats associated with standard candles are their absolute calibration, contamination of the sample from other sources and systematic uncertainties. The absolute calibration mainly depends on their chemical composition and age. To understand the impact of these effects on the distance scale, it is essential to develop methods based on different sample of standard candles. Here we review the fundamental properties of young and intermediate-age distance indicators such as Cepheids, Mira variables and Red Clump stars and the recent developments in their application as distance indicators.