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Search for a Dark Matter-Induced Annual Modulation Signal in NaI(Tl) with the COSINE-100 Experiment

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 نشر من قبل Jay Hyun Jo
 تاريخ النشر 2019
  مجال البحث فيزياء
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We present new constraints on the dark matter-induced annual modulation signal using 1.7 years, of COSINE-100 data with a total exposure of 97.7 kg$cdot$years. The COSINE-100 experiment, consisting of 106 kg of NaI(Tl) target material, is designed to carry out a model-independent test of DAMA/LIBRAs claim of WIMP discovery by searching for the same annual modulation signal using the same NaI(Tl) target. The crystal data show a 2.7 cpd/kg/keV background rate on average in the 2--6 keV energy region of interest. Using a $chi$-squared minimization method we observe best fit values for modulation amplitude and phase of 0.0092$pm$0.0067 cpd/kg/keV and 127.2$pm$45 d, respectively.



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