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Supernova 2007bi como una explosión de inestabilidad de par.

A Gal-Yam1, P Mazzali, E O Ofek

  • 1Benoziyo Center for Astrophysics, Faculty of Physics, The Weizmann Institute of Science, Rehovot 76100, Israel. avishay.gal-yam@weizmann.ac.il

Nature
|December 4, 2009
PubMed
Resumen
Este resumen es generado por máquina.

Las estrellas extremadamente masivas pueden explotar como supernovas de inestabilidad de pares. Las observaciones de la supernova SN 2007bi confirman esto, revelando un núcleo estelar masivo y níquel radiactivo sintetizado.

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Área de la Ciencia:

  • La astronomía y la astrofísica.
  • Evolución Estelar Evolución Estelar
  • Física de las Supernovas Física de las Supernovas

Sus antecedentes:

  • Las estrellas masivas (10-100 masas solares) terminan como supernovas con colapso del núcleo de hierro.
  • Las estrellas extremadamente masivas (>140 masas solares) pueden experimentar supernovas de inestabilidad de pares debido a la producción de pares de electrones-positrones.
  • Las estrellas de transición (100-140 masas solares) pueden exhibir características de ambos tipos de supernovas.

Objetivo del estudio:

  • Para investigar la naturaleza de la supernova SN 2007bi, un objeto luminoso y de lenta evolución.
  • Para probar las predicciones teóricas de las supernovas de inestabilidad de pares.
  • Para explorar la existencia de estrellas extremadamente masivas en galaxias enanas.

Principales métodos:

  • La astronomía de observación se centra en la supernova SN 2007bi.
  • Estimación de la masa del núcleo explosivo.
  • Análisis del níquel radioactivo sintetizado 56.
  • Comparación con los modelos teóricos de las supernovas de inestabilidad de pareja.

Principales resultados:

  • La supernova SN 2007bi tenía una masa estimada de núcleo explosivo de aproximadamente 100 masas solares.
  • Más de 3 masas solares de níquel-56 radiactivo fueron sintetizados durante la explosión.
  • Las observaciones son consistentes con los modelos de supernovas de inestabilidad de pares.

Conclusiones:

  • SN 2007bi proporciona una fuerte evidencia de supernovas de inestabilidad de pares.
  • Las galaxias enanas pueden albergar estrellas extremadamente masivas, que potencialmente exceden el límite de masa estelar galáctica.
  • Estas estrellas masivas podrían ser análogas a las primeras estrellas formadas en el universo.