JiaYu Ou (NCU);Chow-Choong Ngeow(NCU)
[HBS 2006] 40671 is a confirmed long period Mira found in M33. Using observed light curves from Hartmann et al (2006) data, Barsukova et al. (2011) found a period of 665 day for this Mira. In addition to Hartmann's data (2005~2006), we also collected PTF (Palomar Transient Factory) data taken from 2009 to 2016. Combining these two dataset that spanned ~10 years. Furthermore, several nights of LOT data were also collected in R band and I band. We also collected a number of confirmed Miras in I band with periods similar to our target in LMC and SMC from OGLE database to compare to our target. According the OGLE Mira we found majority of Miras are composed by a short pulsation period and a long term variation, hence we also tried to look for additional features using our method, and compared to the light curve of [HBS 2006]40671. Therefore, we can use those information to refine the short period and find out the long term variation. In this poster, we present our latest investigation on the period refinement of this Mira.