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arXiv · 0909.2946

Early-type PMS and MS objects in M16 and the Carina star-forming regions

Christophe Martayan·Michele Floquet·Yves Fremat·Anne-Marie Hubert·Coralie Neiner·Dietrich Baade·Juan Fabregat
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Abstract

Thanks to a variety of pertinent wide-angle facilities (WFI-slitless mode, VLT-FLAMES (Pasquini et al. 2002), SPITZER, 2MASS) it is possible to comprehensively study the nature of early-type objects in star-forming regions like the Eagle Nebula and Carina on large spatial scales. In them, the young open clusters NGC 6611, Trumpler 14, Trumpler 15, Trumpler 16, and their vicinities are of particular interest. With the WFI in its slitless mode (Baade et al. 1999), one can reliably and with little extra effort discriminate in thousands of spectra between intrinsic circumstellar emission as in HBe/Ae stars and diffuse interstellar line emission. The only bias results from the need of the equivalent width and absolute strength of the line emission to be sufficient for detection. VLT-FLAMES spectra combined with infrared data from SPITZER and 2MASS permit the nature of the objects with and without emission-lines to be derived. Following this approach, we report on the discovery and classification of new Herbig Be/Ae stars, pre-main sequence objects, and main sequence stars in these regions. Based on line-width measurements in VLT-FLAMES spectra, the evolution of the rotational velocities between pre-main sequence and main sequence phases is also discussed.

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Christophe Martayan, Michele Floquet, Yves Fremat, Anne-Marie Hubert, Coralie Neiner, Dietrich Baade, Juan Fabregat. 2009-09-16. Early-type PMS and MS objects in M16 and the Carina star-forming regions. https://arxiv.org/abs/0909.2946

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