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The First Direct Search for Inelastic Boosted Dark Matter with COSINE-100

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 Added by Hyun Su Lee
 Publication date 2018
  fields Physics
and research's language is English




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A search for inelastic boosted dark matter (iBDM) using the COSINE-100 detector with 59.5 days of data is presented. This relativistic dark matter is theorized to interact with the target material through inelastic scattering with electrons, creating a heavier state that subsequently produces standard model particles, such as an electron-positron pair. In this study, we search for this electron-positron pair in coincidence with the initially scattered electron as a signature for an iBDM interaction. No excess over the predicted background event rate is observed. Therefore, we present limits on iBDM interactions under various hypotheses, one of which allows us to explore an area of the experimental search for iBDM using a terrestrial detector.



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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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