Weakly interacting massive particle

Weakly interacting massive particles (WIMPs) are hypothetical particles that are one of the proposed candidates for <a href="/facts/Dark_matter/y5HgX55N">dark matter</a>.
There exists no formal definition of a WIMP, but broadly, it is an <a href="/facts/Elementary_particle/CTFDM97U">elementary particle</a> which interacts via <a href="/facts/Gravity/bqAN7DdQ">gravity</a> and any other force (or forces) which is as weak as or weaker than the <a href="/facts/Weak_nuclear_force/f6upmKMs">weak nuclear force</a>, but also non-vanishing in strength. Many WIMP candidates are expected to have been produced thermally in the early Universe, similarly to the particles of the Standard Model according to <a href="/facts/Big_Bang/I5T1vTnv">Big Bang</a> cosmology, and usually will constitute <a href="/facts/Cold_dark_matter/vL4134Kd">cold dark matter</a>. Obtaining the correct abundance of dark matter today via thermal production requires a self-<a href="/facts/Annihilation/tm55RWnf">annihilation</a> <a href="/facts/Cross_section_(physics)/lo014h2D">cross section</a> of 
 
 
 
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 {\displaystyle \langle \sigma v\rangle \simeq 3\times 10^{-26}\mathrm {cm} ^{3}\;\mathrm {s} ^{-1}}
 
, which is roughly what is expected for a new particle in the 100 <a href="/facts/GeV/YMT1fqX9">GeV</a> mass range that interacts via the <a href="/facts/Electroweak_force/QATz4dYF">electroweak force</a>.
Experimental efforts to detect WIMPs include the search for products of WIMP annihilation, including <a href="/facts/Gamma_ray/5Drf913J">gamma rays</a>, <a href="/facts/Neutrino/yGWVfSg2">neutrinos</a> and <a href="/facts/Cosmic_ray/uxCVdTKd">cosmic rays</a> in nearby galaxies and galaxy clusters; direct detection experiments designed to measure the collision of WIMPs with <a href="/facts/Atomic_nucleus/orpIm5Xl">nuclei</a> in the laboratory, as well as attempts to directly produce WIMPs in colliders, such as the <a href="/facts/Large_Hadron_Collider/XWJCFSqT">Large Hadron Collider</a> at <a href="/facts/CERN/y1gwRchm">CERN</a>.
Because <a href="/facts/Supersymmetry/hkWGrMet">supersymmetric</a> 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, in the early 2010s, results from <a href="/facts/Dark_matter/y5HgX55N">direct-detection</a> experiments and the lack of evidence for supersymmetry at the <a href="/facts/Large_Hadron_Collider/XWJCFSqT">Large Hadron Collider</a> (LHC) experiment have cast doubt on the simplest WIMP hypothesis.

Weakly interacting massive particle open-in-new

Weakly interacting massive particle