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La supresión de la formación de estrellas en las galaxias enanas por retroalimentación de calentamiento de granos
Nature
|June 29, 2016
Resumen
El calentamiento fotoeléctrico, no las supernovas, es el principal impulsor que regula la formación de estrellas en las galaxias enanas. Este proceso suprime las tasas de formación estelar en más de diez veces, lo que explica los tiempos de agotamiento de gas observados.
Área de la Ciencia:
- La astrofísica
- Evolución de las galaxias
- Física del medio interestelar
Sus antecedentes:
- El calentamiento fotoeléctrico del polvo interestelar por fotones UV es un mecanismo de calentamiento clave.
- Las simulaciones anteriores sugirieron que las supernovas, no el calentamiento fotoeléctrico, regulan principalmente la formación de estrellas en las galaxias.
- Estudios recientes indican que las leyes de formación estelar dependientes de la metalicidad, consistentes con el calentamiento fotoeléctrico, coinciden mejor con las poblaciones de galaxias observadas.
Objetivo del estudio:
- Investigar la importancia relativa del calentamiento fotoeléctrico y la retroalimentación de las supernovas en la supresión de la formación de estrellas en las galaxias enanas.
- Para probar el impacto de simultáneamente incluyendo el calentamiento fotoeléctrico dependiente del espacio y el tiempo y las ondas de explosión de supernova resueltas en simulaciones de galaxias.
Principales métodos:
- Realizamos una serie de simulaciones avanzadas centradas en galaxias enanas.
- Efectos de calentamiento fotoeléctrico incorporados dependientes del espacio y el tiempo.
- Resolvió la fase de ahorro de energía de las ondas de explosión de supernovas para modelar con precisión la retroalimentación.
Principales resultados:
- Las supernovas por sí solas no pueden explicar los largos tiempos de agotamiento de gas observados en galaxias enanas.
- Se descubrió que el calentamiento fotoeléctrico es el mecanismo dominante que regula la formación de estrellas en las galaxias enanas.
- El calentamiento fotoeléctrico suprimió las tasas de formación estelar en más de un orden de magnitud en comparación con las simulaciones con solo supernovas.
Conclusiones:
- El calentamiento fotoeléctrico juega un papel crítico en la regulación de la formación de estrellas en las galaxias enanas, contrariamente a las suposiciones anteriores.
- Los hallazgos desafían la noción de que las supernovas son los únicos impulsores de las escalas de tiempo de agotamiento de gas.
- El modelado preciso del calentamiento fotoeléctrico es esencial para comprender la evolución de las galaxias y las leyes de formación estelar.
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