The Chemical Composition of Cernis 52 (BD+31° 640)
Abstract
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.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 2009
- DOI:
- 10.1088/0004-637X/706/1/866
- arXiv:
- arXiv:0910.2310
- Bibcode:
- 2009ApJ...706..866G
- Keywords:
-
- ISM: abundances;
- ISM: lines and bands;
- ISM: molecules;
- stars: abundances;
- stars: individual: [C93]52 BD+31 640;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- Accepted for publication in The Astrophysical Journal