The Astrophysical Distance Scale III: Distance to the Local Group Galaxy WLM using Multi-Wavelength Observations of the Tip of the Red Giant Branch, Cepheids, and JAGB Stars

TL;DR

This study compares multiple distance measurement methods for the galaxy WLM, demonstrating that the JAGB method is a reliable, independent tool that agrees well with established techniques, aiding in precise local universe expansion rate estimates.

Contribution

The paper introduces the JAGB method as a new independent distance indicator and validates its accuracy by comparing it with established methods for the galaxy WLM.

Findings

All four distance measurement methods agree within 3%.

JAGB method shows comparable accuracy and precision to traditional methods.

Results support the use of JAGB as a reliable distance calibrator for cosmology.

Abstract

The local determination of the Hubble Constant sits at a crossroad. Current estimates of the local expansion rate of the Universe differ by about 1.7-sigma, derived from the Cepheid and TRGB based calibrations, applied to type Ia supernovae. To help elucidate possible sources of systematic error causing the tension, we show in this study the recently developed distance indicator, the J-region Asymptotic Giant Branch (JAGB) method (arXiv:2005.10792), can serve as an independent cross-check and comparison with other local distance indicators. Furthermore, we make the case that the JAGB method has substantial potential as an independent, precise and accurate calibrator of type Ia supernovae for the determination of H0. Using the Local Group galaxy, WLM we present distance comparisons between the JAGB method, a TRGB measurement at near-infrared (JHK) wavelengths, a TRGB measurement in the optical I band, and a multi-wavelength Cepheid period-luminosity relation determination. We find: $\mu_0$ (JAGB) = 24.97 +/- 0.02 (stat) +/- 0.04 (sys) mag, $\mu_0$ (TRGB NIR) = 24.98 +/- 0.04 stat) +/- 0.07 (sys) mag, $\mu_0$ (TRGB F814W) = 24.93 +/- 0.02 (stat) +/- 0.06 (sys) mag, $\mu_0$ (Cepheids) = 24.98 +/- 0.03 (stat) +/- 0.04 (sys) mag. All four methods are in good agreement, confirming the local self-consistency of the four distance scales at the 3% level, and adding confidence that the JAGB method is as accurate and as precise a distance indicator as either of the other three astrophysically-based methods.