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Indirect dark matter searches in the dwarf satellite galaxy Ursa Major II with the MAGIC Telescopes

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 نشر من قبل Paola Giammaria
 تاريخ النشر 2017
  مجال البحث فيزياء
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The dwarf spheroidal galaxy Ursa Major II (UMaII) is believed to be one of the most dark-matter dominated systems among the Milky Way satellites and represents a suitable target for indirect dark matter (DM) searches. The MAGIC telescopes carried out a deep observation campaign on UMaII between 2014 and 2016, collecting almost one hundred hours of good-quality data. This campaign enlarges the pool of DM targets observed at very high energy (E$gtrsim$50GeV) in search for signatures of dark matter annihilation in the wide mass range between $sim$100 GeV and $sim$100 TeV. To this end, the data are analyzed with the full likelihood analysis, a method based on the exploitation of the spectral information of the recorded events for an optimal sensitivity to the explored dark matter models. We obtain constraints on the annihilation cross-section for different channels that are among the most robust and stringent achieved so far at the TeV mass scale from observations of dwarf satellite galaxies.



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