A Physically-Based Method for Scaling Cepheid Light Curves for Future Distance Determinations

TL;DR

This paper introduces a physically-based method to decompose Cepheid light curves into radius and temperature variations, enabling accurate predictions of their behavior across wavelengths, which aids in precise distance measurements.

Contribution

The paper presents a novel technique for decomposing Cepheid light curves and predicting their multi-wavelength behavior using optical data, improving distance determination methods.

Findings

Can predict light curve shape, amplitude, and phase at any wavelength.

Enables normalization of light curves with a single new observation.

Facilitates precise mean property estimation for Cepheids at new wavelengths.

Abstract

We present a technique for decomposing Cepheid light curves into their fundamental constituent parts; that is, their radius and temperature variations. We demonstrate that any given pair of optical luminosity and color curves can be used to predict the shape, amplitude and phase of a Cepheid's light variation at any other wavelength. With such predictions in hand, a single new observation at any given new wavelength can be used to normalize the properties of the predicted light curve, and in specific, derive a precise value of the time-averaged mean. We suggest that this method will be of great advantage in efficiently observing and precisely obtaining the mean properties of known Cepheids scheduled to be observed at new wavelengths, specifically in the mid-infrared where JWST will be operating.