Instead, the two photons could represent part of the debris produced by the decay of a potentially much more massive particle. (scientificamerican.com)
Scientists currently favor theoretical models that explain dark matter as an exotic massive particle, but so far searches have failed to turn up evidence these hypothetical particles actually exist. (sciencedaily.com)
In 1998, scientists at the DAMA experiment buried deep in Italy's Gran Sasso mountain claimed to have bagged dark matter in the form of a WIMP or a weakly interacting massive particle weighing around 10 gigaelectronvolts (GeV). (newscientist.com)