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¿Es un ion molecular parecido al pireno la causa de la banda de absorción interestelar difusa de 4.430 angstroms?
1NASA-Ames Research Center, Space Science Division, Moffett Field, California 94035, USA.
Nature
|July 2, 1992
Resumen
Las bandas interestelares difusas (DIB, por sus siglas en inglés) son características astronómicas de absorción. Las mediciones de laboratorio sugieren que los cationes de pireno pueden ser responsables de un DIB específico, lo que podría explicar cómo los hidrocarburos aromáticos policíclicos procesan la luz interestelar.
Área de la Ciencia:
- La astronomía y la astrofísica.
- La astroquímica es astroquímica.
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- Las bandas interestelares difusas (DIB) son numerosas características de absorción en los espectros astronómicos.
- Los portadores de los DIB siguen sin ser identificados, con un debate en curso sobre si son gaseosos o basados en granos.
- Los hidrocarburos aromáticos policíclicos (HAP) son candidatos moleculares para algunos portadores de DIB.
Objetivo del estudio:
- Para investigar el espectro óptico del catión pireno (C16H10+) en matrices de laboratorio.
- Para comparar espectros medidos en laboratorio con observaciones astronómicas de DIBs.
- Explorar el papel potencial de los cationes PAH en el procesamiento de la luz interestelar.
Principales métodos:
- Medición de laboratorio del espectro óptico del catión pireno (C16H10+) utilizando matrices de neón y argón.
- Análisis de las características de absorción, incluidas las posiciones de pico y las características del continuo.
- Comparación de datos espectrales con DIB astronómicos conocidos.
Principales resultados:
- El catión pireno exhibe una fuerte característica de absorción cerca de 4.430 angstroms, alineándose con un prominente DIB.
- Este DIB específico, si se atribuye a especies similares al pireno, requeriría el 0,2% de carbono cósmico.
- Se observó un continuo intenso y amplio desde los rayos UV hasta las longitudes de onda visibles para el catión pireno, similar a los cationes naftaleno.
Conclusiones:
- El catión pireno es un candidato plausible para el DIB de 4.430 angstroms.
- Los cationes de HAP pueden poseer una característica continua común responsable de convertir la radiación UV / visible interestelar en infrarrojo.
- Esta investigación contribuye a comprender la composición de la materia interestelar y los procesos de transferencia de energía.
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