Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-08-28
Astronomy and Astrophysics
Astrophysics
17 pages, 10 figures, accepted for publication in Jounal of the Korean Astronomical Society
Scientific paper
In an attempt of clarifying the connection between the photospheric abundance anomalies and the stellar rotation as well as of exploring the nature of "normal A" stars, the abundances of seven elements (C, O, Si, Ca, Ti, Fe, and Ba) and the projected rotational velocity for 46 A-type field stars were determined by applying the spectrum-fitting method to the high-dispersion spectral data obtained with BOES at BOAO. We found that the peculiarities (underabundances of C, O, and Ca; an overabundance of Ba) seen in slow rotators efficiently decrease with an increase of rotation, which almost disappear at v_e sin i > 100 km s^-1. This further suggests that stars with sufficiently large rotational velocity may retain the original composition at the surface without being altered. Considering the subsolar tendency (by several tenths dex below) exhibited by the elemental abundances of such rapidly-rotating (supposedly normal) A stars, we suspect that the gas metallicity may have decreased since our Sun was born, contrary to the common picture of galactic chemical evolution.
Han Inwoo
Kang Dong-Il
Kim Kang-Min
Lee Byeong-Cheol
Takeda Yoichi
No associations
LandOfFree
Rotation and surface abundance peculiarities in A-type stars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Rotation and surface abundance peculiarities in A-type stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rotation and surface abundance peculiarities in A-type stars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-326757