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A groundbreaking new examine printed in Nature Astronomy means that learning an atomic clock on a spacecraft orbiting near the Sun, contained in the orbit of Mercury, could possibly be the important thing to unlocking the mysteries of darkish matter. The analysis presents a probably game-changing strategy to understanding this elusive and enigmatic substance that’s thought to make up a lot of the universe.
Studying an atomic clock on-board a spacecraft contained in the orbit of Mercury and really close to to the Sun is likely to be the trick to uncovering the character of darkish matter, suggests a brand new examine printed in Nature Astronomy.
Dark matter makes up greater than 80 p.c of mass within the universe, nevertheless it has to date evaded detection on Earth, regardless of a long time of experimental efforts. A key element of those searches is an assumption concerning the native density of darkish matter, which determines the variety of darkish matter particles passing by the detector at any given time, and due to this fact the experimental sensitivity. In some fashions, this density may be a lot increased than is normally assumed, and darkish matter can turn out to be extra concentrated in some areas in comparison with others.
One vital class of experimental searches are these utilizing atoms or nuclei, as a result of these have achieved unimaginable sensitivity to alerts of darkish matter. This is feasible, partly, as a result of when darkish matter particles have very small lots, they induce oscillations within the very constants of nature. These oscillations, for instance within the mass of the electron or the interplay power of the electromagnetic drive, modify the transition energies of atoms and nucleii in predictable methods.
Artist’s impression of an area atomic clock used to uncover darkish matter. Credit: Kavli IPMU
An worldwide staff of researchers, Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) Project Researcher Joshua Eby, University of California, Irvine, Postdoctoral Fellow Yu-Dai Tsai, and University of Delaware Professor Marianna S. Safronova, noticed potential in these oscillating alerts. They claimed that in a selected area of the Solar System, between the orbit of Mercury and the Sun, the density of darkish matter could also be exceedingly giant, which might imply distinctive sensitivity to the oscillating alerts.
These alerts could possibly be picked up by atomic clocks, which function by fastidiously measuring the frequency of photons emitted in transitions of various states in atoms. Ultralight darkish matter within the neighborhood of the clock experiment might modify these frequencies, because the oscillations of the darkish matter barely enhance and reduce the photon vitality.
“The more dark matter there is around the experiment, the larger these oscillations are, so the local density of dark matter matters a lot when analyzing the signal,” mentioned Eby.
While the exact density of the darkish matter close to the Sun is just not well-known, the researchers argue that even a comparatively low-sensitivity search might present vital data.
The density of darkish matter is simply constrained within the Solar System by details about planet orbits. In the area between the Sun and Mercury, the planet nearest to the Sun, there may be virtually no constraint. So a measurement onboard a spacecraft might rapidly uncover world-leading limits on darkish matter in these fashions.
The expertise to place their principle to the check already exists. Eby says the NASA Parker Solar Probe, which has been working since 2018 with the assistance of protecting, has traveled nearer to the Sun than any human-made craft in historical past, and is at present working contained in the orbit of Mercury, with plans to maneuver even nearer to the Sun inside a yr.
Atomic clocks in area are already well-motivated for a lot of causes apart from trying to find darkish matter.
“Long-distance area missions, together with doable future missions to Mars, will require exceptional timekeeping as would be provided by atomic clocks in space. A possible future mission, with shielding and trajectory very similar to the Parker Solar Probe, but carrying an atomic clock apparatus, could be sufficient to carry out the search,” said Eby.
Details of their study were published in Nature Astronomy on December 5.
Reference: “Direct detection of ultralight dark matter bound to the Sun with space quantum sensors” by Yu-Dai Tsai, Joshua Eby and Marianna S. Safronova, 5 December 2022, Nature Astronomy.
DOI: 10.1038/s41550-022-01833-6
