ar X iv : a st ro - p h / 99 05 23 3 v 1 1 8 M ay 1 99 9 Three very young HgMn stars in the Orion OB 1 Association
نویسنده
چکیده
We report the detection of three mercury-manganese stars in the Orion OB1 association. HD 37886 and BD–0 • 984 are in the approximately 1.7 million year old Orion OB1b. HD 37492 is in the approximately 4.6 million year old Orion OB1c. Orion OB1b is now the youngest cluster with known HgMn star members. This places an observational upper limit on the time scale needed to produce the chemical peculiarities seen in mercury-manganese stars, which should help in the search for the cause or causes of the peculiar abundances in HgMn and other chemically peculiar upper main sequence stars.
منابع مشابه
ar X iv : a st ro - p h / 98 05 18 9 v 1 1 4 M ay 1 99 8 Isotopic composition of Hg and Pt in slowly rotating HgMn stars
Preliminary results from a study of the isotopic compositions of the elements Hg and Pt in a number of HgMn stars are presented. This work represents an improvement over previous studies thanks to the very high spectral resolution available (R = 118 000) and to the new information on wavelengths and atomic structure of Hg II and Pt II.
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