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Materia de supernova de tipo II en un grano de carburo de silicio del meteorito Murchison
1P. Hoppe, R. Strebel, P. Eberhardt, Physikalisches Institut, Universitat Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland. S. Amari and R. S. Lewis, Enrico Fermi Institute, University of Chicago, Chicago, IL 60637, USA.
Science (New York, N.Y.)
|May 31, 1996
Resumen
El meteorito Murchison fue descubierto.
Área de la Ciencia:
- Cosmoquímica es la cosmoquímica.
- La astrofísica nuclear es una astrofísica nuclear.
- Ciencias planetarias Ciencias planetarias.
Sus antecedentes:
- Los granos de carburo de silicio (SiC) circumstelares son materiales presolares.
- Las anomalías isotópicas en los granos de SiC proporcionan pistas sobre la nucleosíntesis estelar y los procesos de supernova.
Objetivo del estudio:
- Para investigar la composición isotópica del grano de carburo de silicio X57 del meteorito Murchison.
- Para determinar el origen de las relaciones isotópicas anómalas observadas en el grano X57.7.
Principales métodos:
- Análisis isotópico de silicio, calcio y magnesio en grano de SiC X57.
- Modelado de los rendimientos nucleosintéticos de las supernovas de tipo II.
Principales resultados:
- El grano X57 exhibe altas abundancias de calcio-44 y magnesio-26.4 radiogénicos.
- Se detectó una composición isotópica anómala de silicio en el grano X57.7.
- Las relaciones iniciales inferidas fueron: 44Ti/Si = 1,6 x 10(-4), 44Ti/48Ti = 0,37, 26Al/27Al = 0,11.
Conclusiones:
- Los datos isotópicos y elementales de X57 son consistentes con la mezcla de materia de diferentes zonas de una supernova de tipo II de 25 masas solares.
- La alta proporción de 44Ti/Si indica contribuciones de la zona de níquel más interna de la supernova.
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