The Araucaria Project. Multi-band calibrations of the TRGB absolute magnitude

Understand

We present new empirical calibrations of the absolute magnitude of the tip of the red giant branch (TRGB) in the optical I and near-infrared J, H, and K bands in terms of the (V-K)_0, (V-H)_0, and (J-K)_0 colors of the red giant branch.

• Our calibrations are based on the measurements in 19 fields in the Large and Small Magellanic Clouds, which span a wide (V-K)_0 color range of the brightest part of the red giant branch.
• We use a simple edge detection technique based on the comparison of the star count difference in two adjacent bins with the estimated Poisson noise.
• Further, we include the reddening and geometrical corrections, as well as the precise and accurate to 2% distance to the Large Magellanic Cloud.