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La condensación de carbono en el gas de supernova radiactiva
D D Clayton1, W Liu, A Dalgarno
1Department of Physics and Astronomy, Clemson University, Clemson, SC 29634-1911, USA.
Science (New York, N.Y.)
|February 26, 1999
Resumen
La química de la supernova crea polvo de carbono al descomponer el monóxido de carbono, lo que permite que el polvo se forme más rápido que él.
Área de la Ciencia:
- Cosmoquímica es la cosmoquímica.
- La astroquímica es astroquímica.
- Evolución Estelar Evolución Estelar
Sus antecedentes:
- Las supernovas son sitios cruciales para la síntesis de elementos pesados y polvo.
- La formación de monóxido de carbono (CO) típicamente limita la disponibilidad de átomos de carbono libres en las salidas estelares.
- Los granos presolares que se encuentran en los meteoritos proporcionan información sobre las primeras condiciones del sistema solar.
Objetivo del estudio:
- Para investigar los procesos químicos que conducen a la molécula portadora de carbono y la formación de polvo dentro de las supernovas en expansión.
- Para resolver numéricamente las ecuaciones que rigen la abundancia de estas especies.
- Explorar el impacto de la radiactividad en la química del carbono y la formación de polvo.
Principales métodos:
- Solución numérica de las ecuaciones cinéticas químicas que rigen la abundancia de especies.
- Modelado de la química en el interior de una supernova en expansión.
- Análisis del papel de los electrones energéticos de la radiactividad.
Principales resultados:
- Los electrones energéticos de la radioactividad de las supernovas disocian las moléculas de CO, liberando átomos de carbono libres.
- Este proceso mejora el suministro de átomos de carbono disponibles para la formación de polvo.
- El polvo de carbono crece por asociación más rápido de lo que es destruido por la oxidación.
Conclusiones:
- Los interiores de las supernovas pueden ser una fuente significativa de polvo de carbono.
- La disociación del CO por electrones energéticos es un mecanismo clave para permitir la formación de polvo.
- Este hallazgo altera la comprensión del origen de los sólidos de carbono presolar.
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