First result of annual modulation search has been published in Phys. Rev. Lett.

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 yr. The COSINE-100 experiment, consisting of 106 kg of NaI(Tl) target material, is designed to carry out a model-independent test of DAMA/LIBRA’s 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 χ-squared minimization method we observe best fit values for modulation amplitude and phase of 0.0092±0.0067  cpd/kg/keV and 127.2±45.9  d, respectively.

Phys. Rev. Lett. 123, 031302 (2019)

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First direct search of iBDM with COSINE-100 was published in Phys. Rev. Lett as an Editors’ suggestion (April/3th, 2019).

Phys. Rev. Lett. 122, 131802 (2019)

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 dark photon parameter space that has not yet been covered by other experiments. This is the first experimental search for IBDM using a terrestrial detector.

Phys. Rev. Lett. 122, 131802 (2019)

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First annual modulation search from COSINE-100

COSINE-100 report the results from the search for a dark matter-induced annual modulation signal in NaI(Tl) based on 1.7 years of COSINE-100 data. The result is consistent with both a null hypothesis and DAMA/LIBRA’s 2-6 keV best fit value. arXiv:1903.10098

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COSINE-100 initial 59.9 days data indicate no dark-matter induced events, significantly challenging the DAMA claim

(COSINE-100 Collaboration, Nature 564, 83, 2018.)

(Korean) 동아사이언스 , 조선일보 , 한국일보 , 경향신문 , 한겨레 , 국내 10여개 신문 , IBS press

(English) Science Magazine, Physics Today, Economist,  ScienceDaily, ScienceNews, PhysOrg, IBS press

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Neil and Reina interviewed by BBC radio

During IDM2016 conference in Sheffield, UK, Neil and Reina were invited to BBC radio to discuss about sterile neutrino and dark matter. Start listening from 19:20.

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DM-Ice and COSINE-100 in Physics Today

DM-Ice and COSINE-100 were covered in Physics Today article, “Disputed dark-matter results gets put to the test”. PDF version is also available.

External link: http://scitation.aip.org/content/aip/magazine/physicstoday/article/69/7/10.1063/…

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