In
particle physics and
astrophysics,
weakly interacting massive particles, or
WIMPs, are among the last hypothetical particle physics candidates for
dark matter. The term “WIMP” is given to a dark matter particle that was produced by falling out of
thermal equilibrium with the hot dense
plasma of the early universe, although it is often used to refer to any dark matter candidate that interacts with standard particles via a force similar in strength to the
weak nuclear force. Its name comes from the fact that obtaining the correct abundance of dark matter today via thermal production requires a self-
annihilation cross section of , which is roughly what is expected for a new particle in the 100
GeV mass range that interacts via the
electroweak force. Because
supersymmetric extensions of the
standard model of particle physics readily predict a new particle with these properties, this apparent coincidence is known as the “WIMP miracle”, and a stable supersymmetric partner has long been a prime WIMP candidate. However, recent null results from direct detection experiments including
LUX and
SuperCDMS, along with the failure to produce evidence of supersymmetry in the
Large Hadron Collider (LHC) experiment has cast doubt on the simplest WIMP hypothesis. Experimental efforts to detect WIMPs include the search for products of WIMP annihilation, including
gamma rays,
neutrinos and
cosmic rays in nearby galaxies and galaxy clusters; direct detection experiments designed to measure the collision of WIMPs with
nuclei in the laboratory, as well as attempts to directly produce WIMPs in colliders, such as the LHC.