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Diversas fuentes de supernovas de material pre-solar inferidas de los isótopos de molibdeno en los meteoritos
Qingzhu Yin1, Stein B Jacobsen, Katsuyuki Yamashita
1Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 01238, USA.
Nature
|February 23, 2002
Resumen
Los meteoritos primitivos revelan diversos orígenes estelares, ya que su composición isotópica de molibdeno difiere de la media solar. Esto sugiere que el material de múltiples explosiones de supernovas contribuyó al sistema solar temprano.
Área de la Ciencia:
- Cosmoquímica es la cosmoquímica.
- La astrofísica nuclear es una astrofísica nuclear.
- Ciencias planetarias Ciencias planetarias.
Sus antecedentes:
- El material pre-solar en los meteoritos muestra una homogeneización incompleta y un procesamiento a baja temperatura, lo que indica diversas fuentes estelares.
- Las condritas carbonáceas representan la composición promedio del Sistema Solar, con raros granos pre-solares que ofrecen pistas sobre los orígenes.
Objetivo del estudio:
- Para investigar la composición isotópica del molibdeno de las condritas carbonáceas a granel.
- Para determinar si esta composición se alinea con el valor solar promedio aceptado.
- Identificar los procesos nucleosintéticos y las fuentes estelares que contribuyen al material temprano del Sistema Solar.
Principales métodos:
- Análisis de la composición isotópica del molibdeno (Mo) en las condritas carbonáceas a granel.
- Comparación de los datos de meteoritos con los valores solares promedio aceptados.
- Modelado de procesos nucleosintéticos (proceso r y proceso p) para explicar las variaciones isotópicas observadas.
Principales resultados:
- Las condritas carbonáceas a granel exhiben una composición isotópica de molibdeno distinta del valor solar promedio.
- Los datos isotópicos de Mo observados requieren contribuciones de al menos dos eventos de proceso r distintos.
- Se encuentra que la contribución del material del proceso p está desacoplada de las contribuciones del proceso r.
Conclusiones:
- El Sistema Solar temprano incorporó material de diversas fuentes estelares, incluidos múltiples eventos de proceso r y material desacoplado de proceso p de supernovas.
- Estos hallazgos se alinean con la evidencia de isótopos de corta vida y análisis elementales de estrellas pobres en metales, que apoyan un origen complejo de los componentes del Sistema Solar.
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