Annual Fluctuations of WIMPs:

Like the daily changes, there should be annual fluctuations. For example, there should be more collisions of WIMPs in June than in December because the relative velocity is highest in June. Amazingly, DAMA claims to have found this annual modulation! “Early in the year 2000, the DAMA team announced that, for three consecutive years, the event rate ... had shown a small (\( \textrm{about }2\%\)) seasonal variation which peaked in early June and dropped to a minimum in December. They contended that the varying event rate was caused by halo WIMPs...” (Iain Nicolson, 4). This evidence has been checked over and over, and every year since, DAMA has recorded the same results! This is extremely promising for evidence of WIMPs. The only problem is, no other experiment has been able to detect any sort of WIMP signal, so WIMPs are still theoretical until another experiment can confirm DAMA’s. (4, 6)