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Weakly interacting massive particles (WIMPs) are hypothetical particles that are one of the proposed candidates for dark matter.
An axion is a hypothetical elementary particle originally postulated by the Peccei–Quinn theory in 1977 to resolve the strong CP problem in quantum chromodynamics (QCD). If axions exist and have low mass within a specific range, they are of interest as a possible component of cold dark matter.
The DAMA/NaI experiment investigated the presence of dark matter particles in the galactic halo by exploiting the model-independent annual modulation signature. Based on the Earth's orbit around the Sun and the solar system's speed with respect to the center of the galaxy, the Earth should be exposed to a higher flux of dark matter particles around June 1, when its orbital speed is added to the one of the solar system with respect to the galaxy and to a smaller one around December 2, when the two velocities are subtracted. The annual modulation signature is distinctive since the effect induced by dark matter particles must simultaneously satisfy many requirements.
The Cryogenic Dark Matter Search (CDMS) is a series of experiments designed to directly detect particle dark matter in the form of Weakly Interacting Massive Particles. Using an array of semiconductor detectors at millikelvin temperatures, CDMS has at times set the most sensitive limits on the interactions of WIMP dark matter with terrestrial materials. The first experiment, CDMS I, was run in a tunnel under the Stanford University campus. It was followed by CDMS II experiment in the Soudan Mine. The most recent experiment, SuperCDMS, was located deep underground in the Soudan Mine in northern Minnesota and collected data from 2011 through 2015. The series of experiments continues with SuperCDMS SNOLAB, an experiment located at the SNOLAB facility near Sudbury, Ontario in Canada that started construction in 2018 and is expected to start data taking in early 2020s.
PAMELA was a cosmic ray research module attached to an Earth orbiting satellite. PAMELA was launched on 15 June 2006 and was the first satellite-based experiment dedicated to the detection of cosmic rays, with a particular focus on their antimatter component, in the form of positrons and antiprotons. Other objectives included long-term monitoring of the solar modulation of cosmic rays, measurements of energetic particles from the Sun, high-energy particles in Earth's magnetosphere and Jovian electrons. It was also hoped that it may detect evidence of dark matter annihilation. PAMELA operations were terminated in 2016, as were the operations of the host-satellite Resurs-DK1. The experiment was a recognized CERN experiment (RE2B).
The IceCube Neutrino Observatory is a neutrino observatory constructed at the Amundsen–Scott South Pole Station in Antarctica. The project is a recognized CERN experiment (RE10). Its thousands of sensors are located under the Antarctic ice, distributed over a cubic kilometre.
The XENON dark matter research project, operated at the Italian Gran Sasso National Laboratory, is a deep underground detector facility featuring increasingly ambitious experiments aiming to detect hypothetical dark matter particles. The experiments aim to detect particles in the form of weakly interacting massive particles (WIMPs) by looking for rare nuclear recoil interactions in a liquid xenon target chamber. The current detector consists of a dual phase time projection chamber (TPC).
DEAP is a direct dark matter search experiment which uses liquid argon as a target material. DEAP utilizes background discrimination based on the characteristic scintillation pulse-shape of argon. A first-generation detector (DEAP-1) with a 7 kg target mass was operated at Queen's University to test the performance of pulse-shape discrimination at low recoil energies in liquid argon. DEAP-1 was then moved to SNOLAB, 2 km below Earth's surface, in October 2007 and collected data into 2011.
The Large Underground Xenon experiment (LUX) aimed to directly detect weakly interacting massive particle (WIMP) dark matter interactions with ordinary matter on Earth. Despite the wealth of (gravitational) evidence supporting the existence of non-baryonic dark matter in the Universe, dark matter particles in our galaxy have never been directly detected in an experiment. LUX utilized a 370 kg liquid xenon detection mass in a time-projection chamber (TPC) to identify individual particle interactions, searching for faint dark matter interactions with unprecedented sensitivity.
The Cryogenic Rare Event Search with Superconducting Thermometers (CRESST) is a collaboration of European experimental particle physics groups involved in the construction of cryogenic detectors for direct dark matter searches. The participating institutes are the Max Planck Institute for Physics (Munich), Technical University of Munich, University of Tübingen (Germany), University of Oxford, the Comenius University Bratislava (Slovakia) and the Istituto Nazionale di Fisica Nucleare.
Light dark matter, in astronomy and cosmology, are dark matter weakly interacting massive particles (WIMPS) candidates with masses less than 1 GeV. These particles are heavier than warm dark matter and hot dark matter, but are lighter than the traditional forms of cold dark matter, such as Massive Compact Halo Objects (MACHOs). The Lee-Weinberg bound limits the mass of the favored dark matter candidate, WIMPs, that interact via the weak interaction to GeV. This bound arises as follows. The lower the mass of WIMPs is, the lower the annihilation cross section, which is of the order , where m is the WIMP mass and M the mass of the Z-boson. This means that low mass WIMPs, which would be abundantly produced in the early universe, freeze out much earlier and thus at a higher temperature, than higher mass WIMPs. This leads to a higher relic WIMP density. If the mass is lower than GeV the WIMP relic density would overclose the universe.
The DAMA/LIBRA experiment is a particle detector experiment designed to detect dark matter using the direct detection approach, by using a matrix of NaI(Tl) scintillation detectors to detect dark matter particles in the galactic halo. The experiment aims to find an annual modulation of the number of detection events, caused by the variation of the velocity of the detector relative to the dark matter halo as the Earth orbits the Sun. It is located underground at the Laboratori Nazionali del Gran Sasso in Italy.
EDELWEISS is a dark matter search experiment located at the Modane Underground Laboratory in France. The experiment uses cryogenic detectors, measuring both the phonon and ionization signals produced by particle interactions in germanium crystals. This technique allows nuclear recoils events to be distinguished from electron recoil events.
The MAJORANA project is an international effort to search for neutrinoless double-beta (0νββ) decay in 76Ge. The project builds upon the work of previous experiments, notably those performed by the Heidelberg–Moscow and IGEX collaborations, which used high-purity germanium (HPGe) detectors, to study neutrinoless double-beta decay.
The Korea Invisible Mass Search (KIMS), is a South Korean experiment, led by Sun Kee Kim, searching for weakly interacting massive particles (WIMPs), one of the candidates for dark matter. The experiments use CsI(Tl) crystals at Yangyang Underground Laboratory (Y2L), in tunnels from a preexisting underground power plant. KIMS is supported by the Creative Research Initiative program of the Korea Science and Engineering Foundation. It is the first physics experiment located, and largely built, in Korea.
The Particle and Astrophysical Xenon Detector, or PandaX, is a dark matter detection experiment at China Jinping Underground Laboratory (CJPL) in Sichuan, China. The experiment occupies the deepest underground laboratory in the world, and is among the largest of its kind.
The Germanium Detector Array experiment was searching for neutrinoless double beta decay (0νββ) in Ge-76 at the underground Laboratori Nazionali del Gran Sasso (LNGS). Neutrinoless beta decay is expected to be a very rare process if it occurs. The collaboration predicted less than one event each year per kilogram of material, appearing as a narrow spike around the 0νββ Q-value in the observed energy spectrum. This meant background shielding was required to detect any rare decays. The LNGS facility has 1400 meters of rock overburden, equivalent to 3000 meters of water shielding, reducing cosmic radiation background. The GERDA experiment was operated from 2011 onwards at LNGS.
The China Dark Matter Experiment (CDEX) is a search for dark matter WIMP particles at the China Jinping Underground Laboratory. CDEX was the first experiment to be hosted at CJPL, beginning construction of its shield in June 2010, the same month that laboratory construction was completed, and before CJPL's official opening on 12 December.
ANAIS is a dark matter direct detection experiment located at the Canfranc Underground Laboratory (LSC), in Spain.
References
- 1 2 Edwin Cartlidge (Jan 20, 2014). "CoGeNT gives further backing to annual dark-matter variation".
- 1 2 Eric Hand (2010-02-26). "A CoGeNT result in the hunt for dark matter". Nature. Nature News. doi:10.1038/news.2010.97.
- ↑ C. E. Aalseth; CoGeNT collaboration (2011). "Results from a Search for Light-Mass Dark Matter with a P-type Point Contact Germanium Detector". Physical Review Letters. 106 (13): 131301. arXiv: 1002.4703 . Bibcode:2011PhRvL.106m1301A. doi:10.1103/PhysRevLett.106.131301. PMID 21517370. S2CID 24822628.
- ↑ James Dacey (June 2011). "CoGeNT findings support dark-matter halo theory". physicsworld. Retrieved 5 May 2015.
- ↑ Davis, Jonathan; McCabe, Christopher; Boehm, Celine (August 2014). "Quantifying the evidence for Dark Matter in CoGeNT data". Journal of Cosmology and Astroparticle Physics. 1408 (8): 014. arXiv: 1405.0495 . Bibcode:2014JCAP...08..014D. doi:10.1088/1475-7516/2014/08/014. S2CID 54532870.
- ↑ Aalseth, C.E. (5 Feb 2015). "Maximum Likelihood Signal Extraction Method Applied to 3.4 years of CoGeNT Data". arXiv: 1401.6234 [astro-ph.CO].
- ↑ Davis, Jonathan (June 12, 2015). "The Past and Future of Light Dark Matter Direct Detection". Int. J. Mod. Phys. A. 30 (15): 1530038. arXiv: 1506.03924 . Bibcode:2015IJMPA..3030038D. doi:10.1142/S0217751X15300380. S2CID 119269304.
