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Espectro de emisión infrarrojo de las moléculas aromáticas interestelares candidatas
D J Cook1, S Schlemmer, N Balucani
1Department of Chemistry, University of California, Berkeley 94720-1460, USA.
Nature
|March 21, 1996
Resumen
Los hidrocarburos aromáticos policíclicos (HAP) son la clave para la formación estelar. Los espectros de laboratorio muestran que los HAP neutros contribuyen poco a las bandas infrarrojas interestelares, pero sus formas cargadas y los HAP más grandes siguen siendo fuentes probables.
Área de la Ciencia:
- La astroquímica es astroquímica.
- La astrofísica es la astrofísica.
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- El polvo interestelar facilita la formación de hidrógeno molecular, crucial para el nacimiento de las estrellas.
- Los hidrocarburos aromáticos policíclicos (HAP) son compuestos de carbono abundantes en el espacio, que potencialmente forman polvo y explican las emisiones infrarrojas.
- Comprender la emisión de HAP es vital para interpretar los espectros interestelares.
Objetivo del estudio:
- Para investigar los espectros de emisión de varios HAP bajo condiciones interestelares simuladas.
- Para determinar la contribución de los HAP neutros e ionizados a las bandas de emisión infrarrojas no identificadas.
- Identificar fuentes potenciales para las características infrarrojas interestelares observadas.
Principales métodos:
- Adquisición de espectros de emisión de laboratorio de HAP representativos.
- Simulación de las condiciones del medio interestelar para mediciones espectrales.
- Analizar espectros en toda la gama de bandas infrarrojas no identificadas.
Principales resultados:
- Los HAP neutros de tamaño pequeño a moderado mostraron solo una pequeña contribución a las bandas infrarrojas no identificadas.
- Los espectros de emisión sugieren que los HAP ionizados son los contribuyentes más significativos.
- Los HAP más grandes y sus cationes también son candidatos viables para la emisión observada.
Conclusiones:
- Es poco probable que los HAP neutros sean la fuente principal de las bandas de emisión infrarrojas no identificadas.
- Los HAP ionizados y las moléculas de HAP más grandes siguen siendo fuertes candidatos para explicar estas características espectrales interestelares.
- Se justifica una mayor investigación sobre las propiedades espectrales de los HAP ionizados y grandes.
Palabras clave:
La disciplina de la NASA es la exobiología.La Orden de Disciplina de la NASA número 52-10-10 fue aprobada por la NASA.Programa de exobiología de la NASA Programa de exobiología de la NASA.No perteneciente al Centro de la NASA.Más Videos Relacionados
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