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