Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-03-04
Astronomy and Astrophysics
Astrophysics
19 pages, 4 tables, 13 figures, Astronomical Journal, in press
Scientific paper
10.1086/321095
Abundances of 22 elements have been determined from a high-resolution, high signal-to-noise spectrum of HD19994, a star recently announced as harboring an extrasolar planet. A detailed spectroscopic analysis of this stars finds it to have a mass of 1.2+/-0.1Msun. HD19994 is found to be slightly enriched in "metals" relative to the Sun 9[Fe/H]=+0.09+/-0.05 and an average of all metals of [m/H]=+0.13), as are most stars known with extrasolar planets. In a search for possible signatures of accretion of metal-rich gas onto the parent stars (using HD19994 and published abundances for other stars), it is found that a small subset of stars with planets exhibit a trend of increasing [X/H] with increasing condensation temperature for a given element X. This trend may point to the accretion of chemically fractionated solid material into the outer (thin) convection zones of these solar-type stars. It is also found that this small group of stars exhibiting an accretion signature all have large planets orbiting much closer than is found, in general, for stars with planets not showing this peculiar abundance trend, suggesting a physical link between accretion and orbital separation. In addition, the stars showing evidence of fractionated accretion are, on average, of larger mass (1.2Msun) than stars not showing measurable evidence of accretion (1.0Msun).
Cunha Katia
Lazzaro Daniela
Smith Verne V.
No associations
LandOfFree
The Abundance Distribution in the Extrasolar-Planet Host Star HD19994 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 The Abundance Distribution in the Extrasolar-Planet Host Star HD19994, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Abundance Distribution in the Extrasolar-Planet Host Star HD19994 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-22540