The Annual Modulation Signature for Dark Matter: DAMA/LIBRA-Phase1 Results and Perspectives

Figure 1

Experimental residual rate of the single-hit scintillation events measured by DAMA/LIBRA-phase1 in the (2–6) keV energy interval as a function of the time. The data points present the experimental errors as vertical bars and the associated time bin width as horizontal bars. The superimposed curves are the cosinusoidal functions behaviour A cos𝜔(𝑡−𝑡₀) with a period 𝑇=2𝜋/𝜔=1 yr, a phase 𝑡₀=152.5 day (June 2nd) and modulation amplitudes, 𝐴, equal to the central values obtained by best fit on the data points of the entire DAMA/LIBRA-phase1. The dashed vertical lines correspond to the maximum expected for the DM signal (June 2nd), while the dotted vertical lines correspond to the minimum.