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El calentamiento turbulento en los cúmulos de galaxias es más brillante en los rayos X
I Zhuravleva1, E Churazov2, A A Schekochihin3
11] Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, 452 Lomita Mall, Stanford, California 94305-4085, USA [2] Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305-4060, USA.
Nature
|November 4, 2014
Resumen
El calentamiento turbulento en los cúmulos de galaxias equilibra las pérdidas de energía en el medio intracúmulo caliente (ICM). Este proceso resuelve el problema del enfriamiento del gas, explicando las observaciones de los sistemas emisores de rayos X.
Área de la Ciencia:
- La astrofísica es la astrofísica.
- Cosmología Cosmología.
- Física del plasma es la física del plasma.
Sus antecedentes:
- El medio intracluster (ICM) en los cúmulos de galaxias es un plasma caliente que emite rayos X, que constituye la mayoría de la materia bariónica.
- Las pérdidas de energía radiativa en los núcleos del ICM son significativas, lo que lleva al enfriamiento del gas en escalas de tiempo más cortas que la edad del sistema.
- El enfriamiento no controlado contradice las observaciones, lo que sugiere que se requiere un mecanismo de calentamiento para mantener el estado caliente del ICM.
Objetivo del estudio:
- Para investigar el mecanismo responsable del calentamiento del medio intracluster (ICM) y contrarrestar el enfriamiento radiativo.
- Para determinar si el calentamiento turbulento puede compensar adecuadamente las pérdidas de energía en los núcleos de cúmulos de galaxias.
- Explorar la aplicabilidad universal de este mecanismo de calentamiento en varios sistemas ricos en gases que emiten rayos X.
Principales métodos:
- Utilizó datos de rayos X profundos de cúmulos de galaxias.
- Desarrolló y aplicó un nuevo método de análisis de datos para cuantificar directamente la velocidad de calentamiento del ICM.
- Calentamiento evaluado específicamente de la disipación de la turbulencia dentro del ICM.
Principales resultados:
- Se encontró que el calentamiento turbulento era suficiente para compensar el enfriamiento radiativo en el ICM.
- La velocidad de calentamiento de la turbulencia parece equilibrar el enfriamiento radiativo localmente en cada radio.
- Esto sugiere que la turbulencia juega un papel crucial en la regulación de la temperatura del ICM y la prevención del enfriamiento excesivo.
Conclusiones:
- El calentamiento turbulento se identifica como una solución plausible y efectiva para el problema de enfriamiento del gas en los núcleos de los cúmulos de galaxias.
- Este mecanismo probablemente resuelve la discrepancia entre el enfriamiento teórico y las propiedades observadas del ICM.
- Los hallazgos tienen implicaciones más amplias para comprender los sistemas ricos en gas, incluidos los grupos de galaxias y las galaxias elípticas.
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