Nitrogen Abundances in Stars with Planets

Carbon, nitrogen, and oxygen (CNO) are key elements in stellar formation and evolution, and their abundances should also have a significant impact on planetary formation and evolution. We present a detailed spectroscopic analysis of 74 solar-type stars, 42 of which are known to harbour planets.

We determine the nitrogen abundances of these stars and investigate a possible connection between N and the presence of planetary companions. We used VLT/UVES to obtain high-resolution near-UV spectra of our targets. Spectral synthesis of the NH band at 3360A was performed with the spectral synthesis codes MOOG and FITTING. We identify several spectral windows from which accurate N abundance can be obtained. Nitrogen distributions for stars with and without planets show that planet hosts are nitrogen-rich when compared to single stars.

However, given the linear trend between [N/Fe] vs [Fe/H], this fact can be explained as being due to the metal-rich nature of planet hosts. We conclude that reliable N abundances can be derived for metal-rich solar type stars from the near UV molecular band at 3360A. We confirm a linear trend between [N/Fe] and metallicity expected from standard models of Galactic chemical evolution.

CNO Behavior in Planet-harbouring Stars: Nitrogen Abundances in stars with planets

L. Suárez-Andrés, G. Israelian, J.I. González Hernández, V. Zh. Adibekyan, E. Delgado Mena, N. C. Santos, S. G. Sousa
(Submitted on 10 May 2016)

Comments: 10 pages, 8 figures,. Accepted in A&A
Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Earth and Planetary Astrophysics (astro-ph.EP); Astrophysics of Galaxies (astro-ph.GA)
Cite as: arXiv:1605.03049 [astro-ph.SR] (or arXiv:1605.03049v1 [astro-ph.SR] for this version)
Submission history
From: Lucía Suárez-Andrés
[v1] Tue, 10 May 2016 15:09:22 GMT (1253kb,D)
http://arxiv.org/abs/1605.03049