Scientists dig deeper in the search for dark matter

The search for dark matter is hard. Not only is it dark which makes it hard to visibly see, and no shining a torch on it wont help , but also the rare dark matter events that are sought by the cryogenic dark matter search II (CDMSII) could be being masked by cosmic rays striking the earth.

Originally the CDMSII was situated in a tunnel below the Stanford university campus, most probably run by a load of students who never saw the light of day, however it has moved on a long way from those humble beginnings and at the moment the CDMSII is situated in the Soudan mine in Minnesota on the 27th level which is about 2341 ft below the surface, but Dr Marek Kos who is a team member for the experiment outlined details at the high energy physics conference in Paris that the CDMSII could be relocated from Minnesota to the SNOLAB facility in Ontario, Canada, which is about 2 km under ground and this should hopefully stop any interference from those pesky cosmic rays.

Last year in 2009 team members hit the headlines when they reported to have discovered two signals in their detectors that could have been caused by dark matter, however they did report that the chance of these being caused by WIMPS (weakly interacting massive particles) was low. The CDMSII detects these WIMPS at extremely low temperatures and watches out for the release of energy when a particle hits an atom in germanium and silicon crystals within the detectors, it is believed that when a WIMP hits a particle it interacts with the nucleus of the atom and this is known as a nuclear recoil, however the detectors also pick up electron recoils which are interactions between the electrons of an atom and some of these can look allot like nuclear recoils. Hopefully because of the success of last year the CDMSII will be getting better detectors which will be better at distinguishing between nuclear recoils and electron recoils and eventually the team members are hoping that there plans to move deeper underground to the SNOLAB facility will go ahead and that they will be getting ever closer to finally finding that elusive dark matter.