Lithium abundance dispersion in the Pleiades and M 34
نویسندگان
چکیده
منابع مشابه
On the lithium abundance dispersion in late-type Pleiades stars
I present the results of a programme to monitor the strengths of the Li I 6708Å, K I 7699Å and chromospheric Hα lines in a group of cool Pleiades stars. Consistent instrumentation and analysis techniques are used to show that there is no Li I variability on timescales of 1 year that could possibly account for the apparent spread in Li abundances seen in Pleiades stars between effective temperat...
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Lithium abundances in a selected sample of halo stars have been revised by using the new accurate IRFM effective temperatures by Alonso, Arribas & Mart́ınez-Roger (1996a). From 41 plateau stars (Teff > 5700 and [Fe/H]≤ -1.5) we found no evidence for intrinsic dispersion, a tiny trend with Teff and no trend with [Fe/H]. The trend with the Teff is fully consistent with the standard Li isochrones o...
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We have obtained intermediate resolution spectra of eleven candidate brown dwarf members of the Pleiades open cluster using the Keck II telescope and LRIS spectrograph. Our primary goal was to determine the location of the “lithium depletion edge” in the Pleiades and hence to derive a precise age for the cluster. All but one of our 11 program objects have radial velocities appropriate for Pleia...
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The relation between the lithium abundance, ALi, and photospheric activity of solar-type Pleiads is investigated for the first time via acquisition and analysis of B and V-band data. Predictions of activity levels of target stars were made according to the ALi/(B − V) relation and then compared with new CCD photometric measurements. Six sources behaved according to the predictions while one sta...
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We compare the properties of recent samples of the lithium abundances in halo stars to one another and to the predictions of theoretical models including rotational mixing, and we examine the data for trends with metal abundance. We apply two statistical tests to the data: a KS test sensitive to the behavior around the sample median, and Monte Carlo tests of the probability to draw the observed...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2014
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201423379