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arXiv · 2405.00503

The M33 Synoptic Stellar Survey. III. Miras and LPVs in griJHKs

Tarini Konchady·Lucas Macri·Xiaomeng Yan·Jianhua Huang
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Abstract

We present the results of a search for Miras and long-period variables (LPVs) in M33 using griJHKs archival observations from the Canada-France-Hawai'i Telescope. We use multiband information and machine learning techniques to identify and characterize these variables. We recover ~1,300 previously-discovered Mira candidates and identify ~13,000 new Miras and LPVs. We detect for the first time a clear first-overtone pulsation sequence among Mira candidates in this galaxy. We use O-rich, fundamental-mode Miras in the LMC and M33 to derive a distance modulus for the latter of 24.629 +/- 0.046 mag.

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Tarini Konchady, Lucas Macri, Xiaomeng Yan, Jianhua Huang. 2024-05-01. The M33 Synoptic Stellar Survey. III. Miras and LPVs in griJHKs. https://doi.org/10.1093/mnras%2Fstae1140%2F7659844

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