Modeling Mass-Loss and Infrared Excess in Large Magellanic Cloud Cepheids

TL;DR

This study investigates whether Large Magellanic Cloud Cepheids experience stellar winds and mass loss, affecting their infrared luminosities and period-luminosity relations, with implications for understanding their evolution.

Contribution

It introduces a mass-loss model for LMC Cepheids and compares predicted infrared relations with observations, highlighting the significance of mass loss.

Findings

Mass-loss rates range from 10^{-12} to 10^{-7} M_sun/yr.

Predicted infrared PL relations differ from observed, indicating mass loss impacts luminosity.

Evidence suggests non-linearity in the infrared PL relations due to mass loss.

Abstract

The purpose of this preliminary work is to determine if Large Magellanic Cloud (LMC) Cepheids have stellar winds. If a Cepheid undergoes mass loss then at some distance from the star, a fraction of the gas becomes dust, which causes an infrared excess. Mass loss is tested using OGLE II optical observations and SAGE infrared observations for a sample of 488 Cepheids. The resultant mass-loss rates range from $10^{-12}$ to $10^{-7}$ $M_\odot/yr$. Using the mass--loss model we compute infrared stellar luminosities for the sample of Cepheids and compare predicted infrared PL relations with observed relations. The predicted relations not only vary from the observed relations, implying mass loss plays a significant role, but also show evidence for non-linearity. It is determined that mass loss is important for LMC Cepheids.