Period-Luminosity relation for short period Cepheids towards the SMC
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چکیده
We present the Period{Luminosity relation from 290 Cepheids toward the LMC and 597 Cepheids towards the SMC respectively obtained from the monitoring of 1.134.000 and 504.000 stars over 150 nights using the two 4k 8k CCD camera of the Eros2 microlensing project. A slope break of the Period{Luminosity relation has been observed for SMC fundamental mode Cepheids with periods smaller than 2 days. Diierent possible experimental biases, which could explain this eeect have been investigated and could be discarded. This observed slope break could be due to evolutionary eeects combined with convection eeects.
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تاریخ انتشار 2007