The chemical composition of Cernis 52 (BD+31° 640).
HERNANDEZ J.I.G., IGLESIAS-GROTH S., REBOLO R., GARCIA-HERNANDEZ D.A., MANCHADO A. and LAMBERT D.L.
Abstract (from CDS):
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 Teff= 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☉ 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, 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 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.