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The End of the White Dwarf Cooling Sequence in M4: an efficient approach

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 نشر من قبل Luigi Bedin Rolly
 تاريخ النشر 2009
  مجال البحث فيزياء
والبحث باللغة English
 تأليف L. R. Bedin




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We use 14 orbits of ACS observations to reach the end of the white-dwarf cooling sequence in the globular cluster M4. Our photometry and completeness tests show that the end is located at magnitude m_F606W = 28.5+/-0.1, which implies an age of 11.6+/-0.6 Gyr (internal errors only). This is consistent with the age from fits to the main sequence turn-off (12.0+/-1.4 Gyr).



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