The Puzzling Frequencies of CEMP and NEMP Stars

TL;DR

This paper uses binary population simulations to explore the frequencies of CEMP and NEMP stars, revealing that the scarcity of nitrogen-rich stars constrains the initial mass function in metal-poor environments.

Contribution

It provides new insights into how the observed distributions of CEMP and NEMP stars limit models of the initial mass function at low metallicity.

Findings

The observed scarcity of NEMP stars constrains the initial mass function.

Binary population simulations match observed CEMP/NEMP ratios.

Constraints on stellar evolution models at low metallicity.

Abstract

We present the results of binary population simulations of carbon- and nitrogen-enhanced metal-poor (CEMP and NEMP) stars. We show that the observed paucity of very nitrogen-rich stars puts strong constraints on possible modifications of the initial mass function at low metallicity.