Scientists simply constructed a detector that would lastly catch darkish matter

Most experiments thus far have centered on darkish matter particles with plenty that kind of overlap with these of identified elementary particles. If the particles are lighter than an electron, nevertheless, it’s unlikely they’d be detectable with the present normal, specifically detectors based mostly on liquid xenon. So far, no experiment has succeeded in immediately detecting darkish matter. Yet this in itself is a vital discovering, because it exhibits that darkish matter particles don’t exist throughout the mass vary and interplay power examined.

New gadget delicate to lower-energy occasions

An worldwide group led by Laura Baudis, Titus Neupert, Björn Penning and Andreas Schilling from UZH’s Department of Physics has now been capable of probe the existence of darkish matter particles throughout a large mass vary beneath one mega electron volt (MeV). Using an improved superconducting nanowire single-photon detector (SNSPD), the researchers reached a sensitivity threshold of about one-tenth the mass of an electron, above which darkish matter particles are extremely unlikely to exist. “This is the first time we’ve been able to search for dark matter particles in such a low mass range, made possible by a new detector technology,” says first writer Laura Baudis.

In a 2022 proof of idea, the researchers had examined the primary SNSPD gadget that is extremely delicate to lower-energy photons. When a photon strikes the nanowire, it heats it up barely and causes it to immediately lose its superconductivity. The wire briefly turns into an everyday conductor, and the ensuing improve in electrical resistance will be measured.

Detecting smallest darkish matter particles

For their newest experiment, the UZH scientists optimized their SNSPD for darkish matter detection. In specific, they geared up it with superconducting microwires as a substitute of nanowires to maximise its cross part. They additionally gave it a skinny, planar geometry that makes it extremely delicate to adjustments in path. Scientists assume that the Earth passes by means of a “wind” of darkish matter particles, and the particle’s path subsequently shifts over the course of the yr relying on relative velocity. A tool able to selecting up directional adjustments might help to filter out non-dark-matter occasions.

“Further technological improvements to the SNSPD could enable us to detect signals from dark matter particles with even smaller masses. We also want to deploy the system underground, where it will be better shielded from other sources of radiation,” Titus Neupert says. Below the mass vary of electrons, present fashions to explain darkish matter face appreciable astrophysical and cosmological constraints.