OGLE Cepheids have Lower Amplitudes in SMC than in LMC
نویسنده
چکیده
We selected cepheids from the OGLE database for the Magellanic Clouds in the period range 10 ≤ P ≤ 10 days. There were 33 objects in the LMC and 35 in the SMC. We find that the median amplitude of cepheids in the LMC is 18% larger than in the SMC, a 4 σ effect. This implies that the period flux amplitude relation is not universal, and cannot be used to measure distances accurately. Subject headings: galaxies: distances and redshifts – galaxies: Magellanic Clouds – stars: cepheids
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