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Espectro infrarrojo reflejado de una protoestrella masiva en Orión
J I Morino1, T Yamashita, T Hasegawa
1Institute of Astronomy, The University of Tokyo, Osawa, Mitaka, Japan. morino@mtk.ioa.s.u-tokyo.ac.jp
Nature
|June 10, 1998
Resumen
Las estrellas jóvenes masivas en Orión-KL están oscurecidas por el polvo. La luz infrarroja reflejada revela un radio sorprendentemente grande y una alta tasa de acreción, desafiando las teorías actuales de formación estelar.
Área de la Ciencia:
- La astronomía es la astronomía.
- La astrofísica es la astrofísica.
- Formación Estelar Formación Estelar.
Sus antecedentes:
- La fuente infrarroja IRc2 en Orión-KL es una estrella joven y masiva oscurecida por una densa envoltura en forma de disco.
- Su naturaleza exacta y su etapa evolutiva no están claras debido a la visibilidad limitada.
Objetivo del estudio:
- Para investigar las propiedades de la fuente infrarroja oscurecida IRc2.2.
- Para determinar las tasas de acreción y las características físicas de las estrellas jóvenes masivas.
Principales métodos:
- Observaciones de la radiación infrarroja reflejada (aprox. 2 micrómetros) que escapan en la dirección polar.
- Análisis del espectro reflejado, incluidas las líneas de absorción de átomos metálicos y monóxido de carbono.
Principales resultados:
- El espectro reflejado indica una temperatura de la fuente de aproximadamente 4.500 K.
- La luminosidad de la fuente implica un radio de al menos 300 radios solares.
- Las tasas de acreción requeridas se estiman en (5-15) x 10(-3) masas solares por año.
Conclusiones:
- El radio inferido es demasiado grande para los modelos actuales de formación de estrellas masivas con tasas de acreción modestas.
- Las tasas de acreción deben ser significativamente más altas (al menos dos órdenes de magnitud mayores) de lo que normalmente se asume.
- Estos hallazgos desafían las teorías existentes sobre la formación de estrellas masivas.
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