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arXiv · 1708.04047

MAGIC observations of variable very-high-energy gamma-ray emission from PKS1510-089 during May 2015 outburst

Julian Sitarek·Josefa Becerra González·Vandad Fallah Ramazani Elina Lindfors·Giovanna Pedaletti·Fabrizio Tavecchio·Monica Vazquez Acosta·Stefan Larsson·the MAGIC Collaboration·the Fermi-LAT Collaboration·Kiran Baliyan·Navpreet Kaur·Sameer·Svetlana Jorstad·Claudia Raiteri
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Abstract

PKS1510-089 is a flat spectrum radio quasar located at a redshift of 0.36. It is one of only a few such sources detected in very-high-energy (VHE, >100 GeV) gamma rays. Though PKS1510-089 is highly variable at GeV energies, until recently no variability has been observed in the VHE band. In 2015 May PKS1510-089 showed a high state in optical and in the GeV range. A VHE gamma-ray flare was detected with MAGIC at that time, showing the first instance of VHE gamma-ray flux variability on the time scale of days in this source. We will present the MAGIC results from this observation, discuss their temporal and spectral properties in the multi-wavelength context and present modelling of such emission in the external Compton scenario.

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Julian Sitarek, Josefa Becerra González, Vandad Fallah Ramazani Elina Lindfors, Giovanna Pedaletti, Fabrizio Tavecchio, Monica Vazquez Acosta, Stefan Larsson, the MAGIC Collaboration, the Fermi-LAT Collaboration, Kiran Baliyan, Navpreet Kaur, Sameer, Svetlana Jorstad, Claudia Raiteri. 2017-08-14. MAGIC observations of variable very-high-energy gamma-ray emission from PKS1510-089 during May 2015 outburst. https://arxiv.org/abs/1708.04047

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