Near-IR TRGB Distance to Dwarf Elliptical Galaxy NGC 147

Abstract

We report the distance modulus of nearby dwarf elliptical galaxy NGC 147 estimated from the Tip of Red-giant Branch (TRGB) method applying to the color-magnitude diagrams and luminosity functions in the near-infrared JHK bands. Apparent magnitudes of TRGBs in each band are obtained by applying Savitzky-Golay filter to the luminosity functions, and the theoretical absolute magnitudes are estimated from Yonsei-Yale isochrones. The derived values of distance modulus to NGC 147 are (m-M)=23.69±0.12, 23.78±0.17, and 23.85±0.22 for J, H, and K bands, respectively. Distance modulus in bolometric magnitude is also derived as (m-M)=23.87±0.11. We compare the derived values of the TRGB distance modulus to NGC 147 in the near-infrared bands with the previous results in other bands.

Keywords

• TRGB
• distance modulus
• near-infrared
• NGC 147