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arXiv · 0806.0121

The Rosette Eye: the key transition phase in the birth of a massive star

J. Z. Li·M. D. Smith·R. Gredel·C. J. Davis·T. A. Rector
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Abstract

Massive protostars dramatically influence their surroundings via accretion-induced outflows and intense radiation fields. They evolve rapidly, the disk and infalling envelope being evaporated and dissipated in $\sim$ 10$^5$ years. Consequently, they are very rare and investigating this important phase of early stellar evolution is extremely difficult. Here we present the discovery of a key transient phase in the emergence of a massive young star, in which ultraviolet radiation from the new-born giant has just punctured through its natal core. The massive young stellar object AFGL 961 II is readily resolved in the near infrared. Its morphology closely resembles a cat's eye and is here dubbed as the Rosette Eye. Emerging ionized flows blow out an hourglass shaped nebula, which, along with the existence of strong near-infrared excess, suggests the existence of an accretion disk in the perpendicular direction. The lobes of the hourglass, however, are capped with arcs of static H$_{2}$ emission produced by fluorescence. This study has strong implications for our understanding of how massive stars embark on their formation.

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J. Z. Li, M. D. Smith, R. Gredel, C. J. Davis, T. A. Rector. 2008-06-01. The Rosette Eye: the key transition phase in the birth of a massive star. https://doi.org/10.1086/589445

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