Are the Cepheids in Ic 4182 Different from Population I Cepheids in the Galaxy?
نویسندگان
چکیده
Recently, the Cepheids in the spiral galaxy IC 4182 have been in the spotlight due to their use as calibrators for th~ supern~va la d~sta~ce scale: In this process the distance to IC 4182 is obtained by applying the local PopulatIOn I perIod-lumInosity relatIOn to the IC 4182 Cepheid sample. But is it really appropriate to do so? W,e employ t~e technique of Fourier decomposition to compare the light curves of long-period Cephelds In IC 4182 ~Ith thos~ of their Population I counterparts in the Galaxy. At the level of precision of the curren~ data, no ?If!erence IS apparent between the two groups. On the other hand, both groups have light curves which seem distInct from those of a number of Population II Cepheids in the Galaxy. Accordingly, we find no reason why the local period-luminosity relation should not be used to infer the distance to IC 4182. Subject headings: Cepheids ~ distance scale ~ galaxies: individual (IC 4182)
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تاریخ انتشار 2017