Astronomy and Astrophysics
نویسنده
چکیده
We present CCD uvbyβ photometry for stars in the nuclei of the young double cluster h and χ Persei. We find that the reddening is highly variable through the h Per nucleus, increasing from west to east, with values ranging from E(b − y) = 0.328 ± 0.022 in the western part to E(b − y) = 0.465 ± 0.024 in the southeast. Towards χ Per the reddening is fairly constant, with E(b − y) = 0.398 ± 0.025. Both clusters share a common distance modulus of 11.7±0.1 mag., and an age of log t = 7.10± 0.05 years.
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