Título:
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Very high energy gamma-ray observations of strong flaring activity in M87 in 2008 february
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Autores:
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Antoranz Canales, Pedro ;
Barrio Uña, Juan Abel ;
Contreras González, José Luis ;
Fonseca González, Mª Victoria ;
Miranda Pantoja, José Miguel ;
Nieto, Daniel
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Tipo de documento:
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texto impreso
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Editorial:
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IOP Publishing, 2008-09-20
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Dimensiones:
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application/pdf
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Nota general:
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info:eu-repo/semantics/openAccess
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Idiomas:
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Palabras clave:
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Estado = Publicado
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Materia = Ciencias: Física: Electrónica
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Materia = Ciencias: Física: Electricidad
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Materia = Ciencias: Física: Física nuclear
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Tipo = Artículo
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Resumen:
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M87 is the only known nonblazar radio galaxy to emit very high energy (VHE) gamma rays. During a monitoring program of M87, a rapid flare in VHE gamma-rays was detected by the MAGIC telescope in early 2008. The flux was found to be variable above 350 GeV on a timescale as short as 1 day at a significance level of 5.6 sigma. The highest measured flux reached 15% of the Crab Nebula flux. We observed several substantial changes of the flux level during the 13 day observing period. The flux at lower energies (150-350 GeV), instead, is compatible with being constant. The energy spectrum can be described by a power law with a photon index of 2.30 +/- 0.11(stat) +/- 0.20(syst). The observed day-scale flux variability at VHE prefers the M87 core as source of the emission and implies that either the emission region is very compact (just a few Schwarzschild radii) or the Doppler factor of the emitting blob is rather large in the case of a nonexpanding emission region.
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En línea:
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https://eprints.ucm.es/id/eprint/23100/1/MirandaJM52libre.pdf
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