The Chemical Composition of Cernis 52 (BD+31° 640)

González Hernández, J. I.; Iglesias-Groth, S.; Rebolo, R.; García-Hernández, D. A.; Manchado, A.; Lambert, D. L.
Referencia bibliográfica

The Astrophysical Journal, Volume 706, Issue 1, pp. 866-876 (2009).

Fecha de publicación:
11
2009
Número de autores
6
Número de autores del IAC
5
Número de citas
14
Número de citas referidas
14
Descripción
We present an abundance analysis of the star Cernis 52 in whose spectrum we recently reported the naphthalene cation in absorption at 6707.4 Å. This star is on a line of sight to the Perseus molecular complex. The analysis of high-resolution spectra using a χ2-minimization procedure and a grid of synthetic spectra provides the stellar parameters and the abundances of O, Mg, Si, S, Ca, and Fe. The stellar parameters of this star are found to be T eff = 8350 ± 200 K, log(g/cm s2)=4.2 ± 0.4 dex. We derived a metallicity of [Fe/H] = -0.01 ± 0.15. These stellar parameters are consistent with a star of ~2 M sun in a pre-main-sequence evolutionary stage. The stellar spectrum is significantly veiled in the spectral range λλ5150-6730 Å up to almost 55% of the total flux at 5150 Å and decreasing toward longer wavelengths. Using Johnson-Cousins and Two Micron All Sky Survey photometric data, we determine a distance to Cernis 52 of 231+135 -85 pc considering the error bars of the stellar parameters. This determination places the star at a similar distance to the young cluster IC 348. This together with its radial velocity, vr = 13.7 ± 1 km s-1, its proper motion and probable young age support Cernis 52 as a likely member of IC 348. We determine a rotational velocity of vsin i = 65 ± 5 km s-1 for this star. We confirm that the stellar resonance line of Li I at 6707.8 Å is unable to fit the broad feature at 6707.4 Å. This feature should have a interstellar origin and could possibly form in the dark cloud L1470 surrounding all the cluster IC 348 at about the same distance.
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