Measuring the Distance to the Local Group Galaxy NGC 6822 via the JAGB Method and TRGB using Observations from the Magellan Telescope

The Hubble constant (H0), as currently measured indirectly from the Cosmic Microwave Background (CMB), disagrees at the 5-σ level with the measurement of H0 from Cepheid variable stars derived by the SHoES team. Independent local distance ladder measurements of H0 may help to shed light on potential systematic errors in the Cepheid distance scale and thus the Hubble tension. Recently, a new standard candle, the J-region Asymptotic Giant Branch (JAGB) method has been shown to be a precise method for calculating distances, and therefore, for measuring H0 independent of Cepheid variable stars. The JAGB method is based on the constant luminosities of carbon-rich asymptotic giant branch stars in the near-infrared. Using JK observations from the FourStar infrared camera on the Baade Magellan 6.5-meter telescope at Las Campanas, Chile, we present the distance to the Local Group galaxy NGC 6822 using the JAGB method. We also independently measured the distance modulus using the I-band tip of the red giant branch (TRGB) using data from the Baade IMACS camera. We found excellent agreement between our measured TRGB and JAGB distance moduli, demonstrating the JAGB method has comparable accuracy and precision to the TRGB in measuring distances.