Speaker
Description
To investigate possible ways to resolve the Hubble tension other
distance indicators than cepheids, TRGB and SNIa and have seen a renewed
interest in the past years.
The Mira PL-relation is one of them, but in this contribution I want to
discuss the so-called JAGB stars that were introduced by Madore and Freedman in 2020. The name refers to the fact that the sample of interest are (carbon) stars located in region J of the classical 2MASS colour-magnitude diagram of the LMC by Weinberg and Nikolaev (2001)
and that the J-band magnitude is the magnitude of interest to provide the standard candle.
Some have advocated that the mean magnitude in a certain range in (J-K) colour is independent of metallicity and provides the standard candle. However, the situation is more complicated as pointed out in the literature.
Here I will give an introduction, and provide some new results on the SMC and LMC [that confirm results from the literature], and the Milky Wat and M31 as well.
