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Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
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La materia oscura fría y fría se calienta
Andrew Pontzen1, Fabio Governato2
11] Department of Physics and Astronomy, University College London, London WC1E 6BT, UK [2] Oxford Astrophysics, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK [3] Balliol College, University of Oxford, Broad Street, Oxford OX1 3BJ, UK.
Nature
|February 14, 2014
Resumen
Cosmología Cosmología.
Área de la Ciencia:
- Cosmología Cosmología.
- La astrofísica es la astrofísica.
- Física de las partículas Física de las partículas
Sus antecedentes:
- El Modelo Estándar de Cosmología (MEC) postula que la energía oscura y la materia oscura fría constituyen el 95% de la masa-energía del Universo.
- El modelo ΛCDM predice densos 'cusps' de materia oscura en los centros galácticos, lo que contradice las observaciones de 'núcleos' de baja densidad.
Objetivo del estudio:
- Para conciliar el modelo ΛCDM con las distribuciones de materia oscura observadas en los centros galácticos.
- Para investigar el papel de la materia bariónica en la configuración de los perfiles de la materia oscura.
Principales métodos:
- Incorporando la influencia del gas y las estrellas, anteriormente considerados componentes pasivos.
- Modelado de las fluctuaciones del potencial gravitacional causadas por la materia bariónica.
Principales resultados:
- El gas y las estrellas inyectan activamente energía térmica en la materia oscura fría.
- Esta inyección de energía explica las bajas densidades centrales observadas de materia oscura en las galaxias, resolviendo el problema del núcleo-cuspa.
Conclusiones:
- La influencia de la materia bariónica es crucial para las predicciones precisas de la distribución de la materia oscura.
- Los "núcleos" de materia oscura galáctica observados se pueden explicar dentro del marco ΛCDM mediante la inclusión de retroalimentación bariónica.
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