CDMS Results!
CDMS stands for Cold Dark Matter Search. The experiments objectives are to find evidence for the existence of dark matter–matter that we have so far only been able to see due to its gravitational interaction–that is low in kinetic energy, as opposed to “hot” dark matter like neutrinos. The most compelling form of dark matter are Weakly Interacting Massive Particles, or WIMPs. They’ve just released their 2007-2008 results, which you can find here, straight from the source: http://cdms.berkeley.edu/
So what have they seen? One strong point of CDMS is a very intense understanding of their background, that is, events that look like they could be coming from WIMPs, but probably aren’t for a variety of reasons. So after all is said and done and they’ve isolated the WIMP signal they are left with two events. But this still doesn’t mean they’ve discovered dark matter! In their arXiv paper they go on to say that there is a 23% probability of background creating two or more events in the region that would get past their filters. So there’s about one out of four chances that it was missed background, so as they say, “These expectations indicate that the result of this analysis cannot be interpreted as significant evidence for WIMP interactions, but we cannot reject either event as signal.”
And hopefully your excitement is not oscillating too rapidly, but in case your disappointed by the news that no especially compelling evidence for WIMP interactions has been found, they will be able to set some awesome upper limits on the WIMP-nucleon cross-section.
