论文标题
M33 CFHT/MEGACAM调查的Cepheids
M33 Cepheids from CFHT/MegaCAM survey
论文作者
论文摘要
在本文中，我们分析了Hartman等人获取的M33的Sloan G，R，i。 （2006年）在加拿大 - 哈瓦伊望远镜上使用Megacam。为了确定与M33星系的距离，我们执行了几个分析步骤，以识别其头孢虫种群。我们使用Lomb-Scargle算法来找到周期性并在视觉上识别出1989年的周期性变为星。由于头孢虫占据了颜色数字图的特定区域，因此将头孢虫与其他变量区分开来，因此我们使用头孢菌不稳定性条的预期位置将M33中的cepheids与其他变量降低。这导致了我们的1622个变量样本，这是迄今为止M33中已知的最大的头孢虫样品。我们进一步将这些头孢菌分类为不同的子类别，并使用基本模式的头孢虫来估计不同过滤器中M33的距离模量：μ= 25.044 +/- 0.083 mag在G滤波器中，μ= 24.886 +/- 0.074 mag in R Filter in r Filter和μ= 24.785 +/---0.085 +/---0688.0688.0688.068。这些结果与以前的结果一致。
In this paper we analyze Sloan g,r,i archival imaging data of M33 taken by Hartman et al. (2006) using Megacam at the Canada-France-Hawaii Telescope. To determine the distance to the M33 galaxy, we performed several analytical steps to identify its Cepheid population. We used the Lomb-Scargle algorithm to find periodicity and visually identified 1989 periodic variable stars. Since Cepheids occupy a specific region of the color-magnitude diagram, to differentiate Cepheids from other variables we used the expected position of the Cepheid instability strip to down-select Cepheids in M33 from other variables. This led to our sample of 1622 variables, the largest Cepheid sample known in M33 to date. We further classified these Cepheids into different subclasses, and used the fundamental mode Cepheids to estimate distance moduli for M33 in different filters: μ= 25.044+/-0.083 mag in the g filter, μ= 24.886+/-0.074 mag in the r filter, and μ= 24.785+/-0.068 mag for the i filter. These results are in agreement with previous results.
