The Araucaria Project. Distances to Nine Galaxies Based on a Statistical Analysis of their Carbon Stars (JAGB Method)

Bartłomiej Zgirski; Grzegorz Pietrzyński; Wolfgang Gieren; Marek Górski; Piotr Wielgórski; Paulina Karczmarek; Fabio Bresolin; Pierre Kervella; Rolf-Peter Kudritzki; Jesper Storm; Dariusz Graczyk; Gergely Hajdu; Weronika Narloch; Bogumił Pilecki; Ksenia Suchomska; Mónica Taormina

arXiv · 2105.02120

The Araucaria Project. Distances to Nine Galaxies Based on a Statistical Analysis of their Carbon Stars (JAGB Method)

Bartłomiej Zgirski·Grzegorz Pietrzyński·Wolfgang Gieren·Marek Górski·Piotr Wielgórski·Paulina Karczmarek·Fabio Bresolin·Pierre Kervella·Rolf-Peter Kudritzki·Jesper Storm·Dariusz Graczyk·Gergely Hajdu·Weronika Narloch·Bogumił Pilecki·Ksenia Suchomska·Mónica Taormina

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Abstract

Our work presents an independent calibration of the J-region Asymptotic Giant Branch (JAGB) method using Infrared Survey Facility (IRSF) photometric data and a custom luminosity function profile to determine JAGB mean magnitudes for nine galaxies. We determine a mean absolute magnitude of carbon stars of $M_{LMC}=-6.212 \pm 0.010$ (stat.) $\pm 0.030$ (syst.) mag. We then use near-infrared photometry of a number of nearby galaxies, originally obtained by our group to determine their distances from Cepheids using the Leavitt law, in order to independently determine their distances with the JAGB method. We compare the JAGB distances obtained in this work with the Cepheid distances resulting from the same photometry and find very good agreement between the results from the two methods. The mean difference is 0.01 mag with an rms scatter of 0.06 mag after taking into account seven out of the eight analyzed galaxies that had their distances determined using Cepheids. The very accurate distance to the Small Magellanic Cloud (SMC) based on detached eclipsing binaries (Graczyk et al. 2020) is also in very good agreement with the distance obtained from carbon stars.

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Bartłomiej Zgirski, Grzegorz Pietrzyński, Wolfgang Gieren, Marek Górski, Piotr Wielgórski, Paulina Karczmarek, Fabio Bresolin, Pierre Kervella, Rolf-Peter Kudritzki, Jesper Storm, Dariusz Graczyk, Gergely Hajdu, Weronika Narloch, Bogumił Pilecki, Ksenia Suchomska, Mónica Taormina. 2021-05-05. The Araucaria Project. Distances to Nine Galaxies Based on a Statistical Analysis of their Carbon Stars (JAGB Method). https://arxiv.org/abs/2105.02120

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