Tip of the red-giant branch (TRGB) is a primary distance indicator used in astronomy. It uses the luminosity of the brightest red-giant-branch stars in a galaxy as a standard candle to gauge the distance to that galaxy.

Jul 25, 2018 · The cluster contains many TRGB stars whose distances have been established by several other methods at around 16,000 light years. These stars have made it possible to calibrate the TRGB method, making it one of the most accurate for measuring galaxies up to 45 million light years.

But as you count fainter and fainter stars, you will eventually reach stars on the galaxy's TRGB -- at which point suddenly lots of stars will appear (because these are the brightest members of the main population of the galaxy)

Jul 25, 2019 · The TRGB is a prominent feature in the color–magnitude diagram (CMD), defining the upper boundary of red giant branch (RGB) stars. The TRGB feature arises at the onset of core helium burning in low-mass stars. RGB stars reaching the tip have hydrogen shell-burning supported by an electron-degenerate helium core.

A low-mass star that is fusing hydrogen in a thin shell surrounding its inert Helium core will increase in luminosity and ascend the H-R diagram along the red giant branch. After the RGB star's once-inert core reaches temperatures to fuse He, a …

Mar 4, 2020 · Here we present a multi-wavelength, VIJHK absolute calibration of the TRGB based on observations of TRGB stars in the Large Magellanic Cloud (LMC), grounded on a geometric distance, determined by detached eclipsing binaries (DEBs).

Jun 6, 2023 · These simulations incorporate a luminosity function composed of 2 mag of red giant branch (RGB) stars leading up to the tip, with asymptotic giant branch (AGB) stars contributing exclusively to the luminosity function for at least a magnitude above the RGB tip.

Feb 4, 2020 · Abstract: The Tip of the Red Giant (TRGB) method provides one of the most accurate and precise means of measuring the distances to nearby galaxies. Here we present a VIJHK absolute calibration of the TRGB based on observations of TRGB stars in the Large Magellanic Cloud (LMC),grounded on detached eclipsing binaries (DEBs).

Jan 9, 2024 · The tip of the red giant branch (TRGB) allows for the measurement of precise and accurate distances to nearby galaxies, based on the brightest ascent of low-mass red giant branch stars before they...

May 30, 2023 · We review the theoretical underpinnings, evolutionary status, calibrations and current applications of three bright Population II extragalactic distance indicators: Tip of the Red Giant Branch (TRGB) stars, RR Lyrae variables and J-Branch Asymptotic Giant Branch (JAGB/Carbon) stars.