The opening of the action would mark a key episode in the history of science. This hypothetical particle could simultaneously solve two main problems of modern physics: the problem of charge and parity in strong interaction and the mystery of dark matter. Despite the high scientific interest in finding it, the demand for high frequency radios – above 6 GHz – has been almost put aside due to the lack of high-sensitivity technology that can be built at a reasonable price. So far.
The Canary Institute of Astrophysics (IAC) will participate in an international collaboration to develop DALI (Dark photons and Axion-Similar to a particle interferometer) experiment, a telescope with astroparticles for dark matter, whose scientific goal is the search for axions and paraphotons in the band from 6 to 60 GHz. The prototype, proof of concept, is currently in the design and production phase at IAC. The White paper describing the experiment has been accepted for publication in Journal of Astroparticle Cosmology and Physics (JCAP).
Predicted by theory in the 1970s, an axion is a hypothetical low-mass particle that interacts weakly with standard particles such as nucleons and electrons, as well as with photons. These proposed interactions are studied to try to find the axiom with different types of instruments. A promising technique is to study the interaction of axions with standard photons.
Axions “mix” with photons under the action of a strong external magnetic field, such as those obtained from superconducting magnets in particle detectors or those used for medical diagnostics by magnetic resonance imaging, and produce a weak radio or microwave signal. This signal has been sought in various experiments since the late 1980s, and it is simply the signal we want to find now with DALI, albeit in a new, almost unexplored range of parameters that will be available for the first time thanks to this experiment. “, Explains Javier De Miguel, an IAC researcher and the first author of the study.
The first axial detectors, made in the 1980s and 1990s, used a resonant cavity that amplified inside a supermagnet the weak microwave signal provided by the axion, trying to bring it into a power range detectable by scientific instruments. Unfortunately, the size of the cavity is inversely proportional to the scanning frequency and, for axion, the cavities were too small to be made for frequencies higher than about 6 GHz.
For this reason, the new experiment combines the most promising high-frequency scanning techniques and incorporates it into a practical design, to which is added the capacity of astroparticle axial dark matter detectors. Thus, DALI includes a powerful superconducting magnet, an axion detector with a new resonator that makes the weak signal caused by the axions detectable, and mounting altazimuth, allowing it to scan objects and regions in the sky for dark matter.
In this way, DALI can help detect the axion, a pseudoscalar particle whose nature is similar to that of the Higgs boson, discovered in 2012 in CERN, and a promising candidate for dark matter. Dark matter is a major component of the universe that interacts very weakly with ordinary matter and is therefore very difficult to detect directly, but whose discovery would allow us to explain the rotation curves of spiral galaxies and why the formation of a structure in the universe evolved. , on which it has developed so far, among other mysteries.
Reference: “Telescope with dark matter, probing the range from 6 to 60 GHz” by Javier De Miguel, April 28, 2021, Journal of Astroparticle Cosmology and Physics.
DOI: 10.1088 / 1475-7516 / 2021/04/075