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Dark matter detectors, experiments attempting to detect dark matter, have been deployed and operated over the past few decades. Since it is unknown what dark matter consists of, such detectors vary, based upon the numerous theories regarding its makeup. Regarding MACHOs, a number of surveys (POINT-AGAPE, GMAN, EROS, OGLE, the MACHO Project) watched for gravitational microlensing that would reveal the presence of enough unseen substantial objects to account for dark matter, but they did not and in fact analysis led to claims that there cannot be enough MACHOs to account for the bulk of dark matter. More recent microlensing surveys that are generally aimed at extra-solar planet discovery (e.g., MOA), in effect, continue checking for this possibility.
Searches for some kind of unknown, undetected particle must be based on some assumptions. The WIMP theory led to ideas about the particle's mass and such a particle is presumed to be neutral. Among the past and present experiments looking to sense such dark matter particles are PICO experiment, XENON10, LUX, and ZEPLIN. Also, any as-yet unseen particle identified in current particle-physics experiments would clearly receive attention as a possibility.
Another experiment, AMS-02 looks for dark matter annihilation: some theoretical dark matter particles would be subject to it, i.e., occurring both as matter and antimatter, or as Majorana particles, and the theory is that encounters between particles would be everywhere but could be rare enough to require very careful observation to detect.
Another strategy has been to detect particle interactions within a shielded detector (eliminating cosmic rays), looking for an expected pattern: a sinusoidal variation in number of interactions over the course of a year (an annual modulation). Over an Earth orbital period, the Earth is sometimes orbiting closer to the same direction as the Sun's orbital motion around the galactic center, and sometimes its orbit is closer to the opposite direction, leading to a cycle of shifting speeds at which the Earth is moving through the galaxy. If the dark matter particles move in all directions that are evenly spread randomly (as do molecules in a gas), then the Earth should encounter more when it is moving faster through the galaxy. Dark matter must be something with gravity but that does not interact with the stars through EMR, and the particle-velocities throughout the dark matter halo are presumed to have settled into randomness analogous to that of a gas, more or less like a Maxwell-Boltzmann distribution. Such detectors use scintillators designed to interact with particles within the expected WIMP mass-range and record such detections over the course of years. Examples include DAMA/LIBRA, COSINE-100, and ANAIS-112.