اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدThe bottom of the white dwarf cooling sequence in the old open cluster NGC 2158
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تأليف
L. R. Bedin
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We use 10 orbits of Advanced Camera for Surveys observations to reach the end of the white dwarf cooling sequence in the solar-metallicity open cluster NGC 2158. Our photometry and completeness tests show that the end falls at magnitude m_F606W = 27.5 +/- 0.15, which implies an age between ~1.8 and ~2.0 Gyr, consistent with the age of 1.9 +/- 0.2 Gyr obtained from fits to the main-sequence turn-off. The faintest white dwarfs show a clear turn toward bluer colors, as predicted by theoretical isochrones.
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