![]() | This article has multiple issues. Please help improve it or discuss these issues on the talk page . (Learn how and when to remove these template messages)
|
MultiDark (MULTImessenger Approach for DARK Matter Detection) is a Spanish project, with a stated goal of contributing to the identification and detection of dark matter. [1]
The project is a grouping effort, involving many researchers in the Spanish community with a special interest in dark matter. It began on 17 December 2009 and was funded for five years. The project is supported by Consolider-Ingenio, a programme of the Ministry of Economy and Finance. [2]
Physical cosmology is a branch of cosmology concerned with the study of cosmological models. A cosmological model, or simply cosmology, provides a description of the largest-scale structures and dynamics of the universe and allows study of fundamental questions about its origin, structure, evolution, and ultimate fate. Cosmology as a science originated with the Copernican principle, which implies that celestial bodies obey identical physical laws to those on Earth, and Newtonian mechanics, which first allowed those physical laws to be understood.
In astronomy, dark matter is a hypothetical form of matter that appears not to interact with light or the electromagnetic field. Dark matter is implied by gravitational effects which cannot be explained by general relativity unless more matter is present than can be seen. Such effects occur in the context of formation and evolution of galaxies, gravitational lensing, the observable universe's current structure, mass position in galactic collisions, the motion of galaxies within galaxy clusters, and cosmic microwave background anisotropies.
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.
Brane cosmology refers to several theories in particle physics and cosmology related to string theory, superstring theory and M-theory.
In physics, mirror matter, also called shadow matter or Alice matter, is a hypothetical counterpart to ordinary matter.
The cuspy halo problem is a discrepancy between the inferred dark matter density profiles of low-mass galaxies and the density profiles predicted by cosmological N-body simulations. Nearly all simulations form dark matter halos which have "cuspy" dark matter distributions, with density increasing steeply at small radii, while the rotation curves of most observed dwarf galaxies suggest that they have flat central dark matter density profiles ("cores").
A strongly interacting massive particle (SIMP) is a hypothetical particle that interacts strongly between themselves and weakly with ordinary matter, but could form the inferred dark matter despite this.
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.
In particle physics, the lightest supersymmetric particle (LSP) is the generic name given to the lightest of the additional hypothetical particles found in supersymmetric models. In models with R-parity conservation, the LSP is stable; in other words, it cannot decay into any Standard Model particle, since all SM particles have the opposite R-parity. There is extensive observational evidence for an additional component of the matter density in the universe, which goes under the name dark matter. The LSP of supersymmetric models is a dark matter candidate and is a weakly interacting massive particle (WIMP).
The axino is a hypothetical elementary particle predicted by some theories of particle physics. Peccei–Quinn theory attempts to explain the observed phenomenon known as the strong CP problem by introducing a hypothetical real scalar particle called the axion. Adding supersymmetry to the model predicts the existence of a fermionic superpartner for the axion, the axino, and a bosonic superpartner, the saxion. They are all bundled up in a chiral superfield.
In astronomy and cosmology, the dark fluid theory attempt to explain dark matter and dark energy in a single framework, as suggested by cosmologist Alexandre Arbey in 2005. The theory proposes that dark matter and dark energy are not separate physical phenomena, nor do they have separate origins, but that they are strongly linked together and can be considered as two facets of a single fluid. At galactic scales, the dark fluid behaves like dark matter, and at larger scales its behavior becomes similar to dark energy.
In physical cosmology and astronomy, dark energy is an unknown form of energy that affects the universe on the largest scales. Its primary effect is to drive the accelerating expansion of the universe. Assuming that the lambda-CDM model of cosmology is correct, dark energy is the dominant component of the universe, contributing 68% of the total energy in the present-day observable universe while dark matter and ordinary (baryonic) matter contribute 26% and 5%, respectively, and other components such as neutrinos and photons are nearly negligible. Dark energy's density is very low: 6×10−10 J/m3, much less than the density of ordinary matter or dark matter within galaxies. However, it dominates the universe's mass–energy content because it is uniform across space.
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.
Marek Gaździcki is a Polish high-energy nuclear physicist, and the initiator and spokesperson of the NA61/SHINE experiment at the CERN Super Proton Synchrotron (SPS).
In cosmology, primordial black holes (PBHs) are hypothetical black holes that formed soon after the Big Bang. In the inflationary era and early radiation-dominated universe, extremely dense pockets of subatomic matter may have been tightly packed to the point of gravitational collapse, creating primordial black holes without the supernova compression typically needed to make black holes today. Because the creation of primordial black holes would pre-date the first stars, they are not limited to the narrow mass range of stellar black holes.
In high-energy nuclear physics, strangeness production in relativistic heavy-ion collisions is a signature and diagnostic tool of quark–gluon plasma (QGP) formation and properties. Unlike up and down quarks, from which everyday matter is made, heavier quark flavors such as strange and charm typically approach chemical equilibrium in a dynamic evolution process. QGP is an interacting localized assembly of quarks and gluons at thermal (kinetic) and not necessarily chemical (abundance) equilibrium. The word plasma signals that color charged particles are able to move in the volume occupied by the plasma. The abundance of strange quarks is formed in pair-production processes in collisions between constituents of the plasma, creating the chemical abundance equilibrium. The dominant mechanism of production involves gluons only present when matter has become a quark–gluon plasma. When quark–gluon plasma disassembles into hadrons in a breakup process, the high availability of strange antiquarks helps to produce antimatter containing multiple strange quarks, which is otherwise rarely made. Similar considerations are at present made for the heavier charm flavor, which is made at the beginning of the collision process in the first interactions and is only abundant in the high-energy environments of CERN's Large Hadron Collider.
Multi-messenger astronomy is astronomy based on the coordinated observation and interpretation of signals carried by disparate "messengers": electromagnetic radiation, gravitational waves, neutrinos, and cosmic rays. They are created by different astrophysical processes, and thus reveal different information about their sources.
Direct detection of dark matter is the science of attempting to directly measure dark matter collisions in Earth-based experiments. Modern astrophysical measurements, such as from the Cosmic Microwave Background, strongly indicate that 85% of the matter content of the universe is unaccounted for. Although the existence of dark matter is widely believed, what form it takes or its precise properties has never been determined. There are three main avenues of research to detect dark matter: attempts to make dark matter in accelerators, indirect detection of dark matter annihilation, and direct detection of dark matter in terrestrial labs. The founding principle of direct dark matter detection is that since dark matter is known to exist in the local universe, as the Earth, Solar System, and the Milky Way Galaxy carve out a path through the universe they must intercept dark matter, regardless of what form it takes.
Daniel S. Akerib is an American particle physicist and astrophysicist. He was elected in 2008 a fellow of the American Physical Society (APS).
{{cite journal}}
: CS1 maint: numeric names: authors list (link){{cite journal}}
: CS1 maint: numeric names: authors list (link)