English

Difference of photometric properties between regular and non-regular Miras in the Magellanic Clouds

Solar and Stellar Astrophysics 2022-04-13 v1 Astrophysics of Galaxies

Abstract

Mira variables are asymptotic giant branch pulsating stars with long pulsation periods and large amplitudes in optical bands. By applying the random forest algorithm to the I-band light curves for the Miras in the Magellanic Clouds, we have classified these Miras into regular Miras and non-regular Miras. Wherein non-regular Miras exhibit a long-term variation in addition to their primary pulsation periods. Our results confirm that the period-luminosity relation for maximum light has a smaller dispersion, but only occurs on the regular oxygen-rich (O-rich) Miras, which we recommend to be applied in future distance scale work. We have also collected multi-band photometry for these Miras to perform a spectral-energy-distribution (SED) fitting with stellar and dust components, showing that a significant fraction of dust is present around the non-regular Miras. According to our results, we believe that the periodic long-term variations seen in the non-regular Miras might be due to the presence of dust.

Keywords

Cite

@article{arxiv.2203.00896,
  title  = {Difference of photometric properties between regular and non-regular Miras in the Magellanic Clouds},
  author = {Jia-Yu Ou and Chow-Choong Ngeow},
  journal= {arXiv preprint arXiv:2203.00896},
  year   = {2022}
}