Red Supergiant Stars as Cosmic Abundance Probes. III. NLTE effects in J-band Magnesium lines
arXiv:1412.6527 · doi:10.1088/0004-637X/804/2/113
Abstract
Non-LTE calculations for Mg I in red supergiant stellar atmospheres are presented to investigate the importance of non-LTE for the formation of Mg I lines in the NIR J-band. Recent work using medium resolution spectroscopy of atomic lines in the J-band of individual red supergiant stars has demonstrated that technique is a very promising tool to investigate the chemical composition of the young stellar population in star forming galaxies. As in previous work, where non-LTE effects were studied for iron, titanium and silicon, substantial effects are found resulting in significantly stronger Mg I absorption lines. For the quantitative spectral analysis the non-LTE effects lead to magnesium abundances significantly smaller than in LTE with the non-LTE abundance corrections varying smoothly between -0.4 dex and -0.1 dex for effective temperatures between 3400 K and 4400 K. We discuss the physical reasons of the non-LTE effects and the consequences for extragalactic J-band abundance studies using individual red supergiants in the young massive galactic double cluster h and chi Persei.
21 pages, 51 figures, accepted for publication in ApJ
References in corpus (6)
- A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
- Red Supergiant Stars as Cosmic Abundance Probes: KMOS Observations in NGC 6822
- Experimental Mg I oscillator strengths and radiative lifetimes for astrophysical applications on metal-poor stars - New data for the Mg I b triplet
- Stellar Metallicity of the Extended Disk and Distance of the Spiral Galaxy NGC 3621
- A New Method for Measuring Metallicities of Young Super Star Clusters
- Quantitative Spectroscopic J-band Study of Red Supergiants in Perseus OB-1
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