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Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
Un origen en el Universo local para algunas ráfagas cortas de rayos gamma
N R Tanvir1, R Chapman, A J Levan
1Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK. nrt@star.herts.ac.uk
Nature
|December 16, 2005
Resumen
Las ráfagas cortas de rayos gamma (GRB) tienen un origen misterioso. Este estudio revela que el 10-25% de los GRB cortos se originan en galaxias cercanas, correlacionando sus ubicaciones con las posiciones de las galaxias locales.
Área de la Ciencia:
- * Astrofísica es la astrofísica.
- * Astrofísica de alta energía.
- * Cosmología observacional.
Sus antecedentes:
- * Las explosiones de rayos gamma (GRB) se clasifican por duración: larga (T90 > 2 s) y corta (T90 < 2 s).
- * Los GRB largos están vinculados a supernovas de colapso de núcleo, mientras que los orígenes de los GRB cortos no estaban claros anteriormente.
- * Las llamaradas gigantes de repetidores blandos de rayos gamma plantearon preguntas sobre los orígenes de GRB cortos en galaxias cercanas.
Objetivo del estudio:
- * Para investigar el origen de las ráfagas cortas de rayos gamma (GRB).
- * Para determinar si los GRB cortos están asociados con galaxias locales.
Principales métodos:
- * Correlación de las ubicaciones de GRBs cortos previamente observados con las posiciones de las galaxias en el Universo local.
- * Analizando los datos de desplazamiento al rojo (z < 0.025) para eventos GRB cortos.
Principales resultados:
- * Se encontró una correlación significativa entre las ubicaciones cortas de GRB y las galaxias cercanas.
- * Se descubrió que entre el 10% y el 25% de los GRB cortos se originan en desplazamientos al rojo bajos (z < 0,025).
Conclusiones:
- * Los GRB cortos no son exclusivamente eventos extragalácticos con altos desplazamientos al rojo.
- * Una fracción notable de GRBs cortos probablemente se originan en fuentes dentro del Universo local, posiblemente similar a las llamaradas gigantes de repetidores de rayos gamma suaves.
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