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hubie [soylentnews.org] writes:

No, scientists still don't know what dark matter is. But MSU scientists helped uncover new physics while looking for it. [msu.edu]

"We started out looking for dark matter and we didn't find it," he said. "Instead, we found other things that have been challenging for theory to explain."

[...] In particular, the team confirmed that when an atom's core, or nucleus, is overstuffed with neutrons, it can still find a way to a more stable configuration by spitting out a proton instead.

[...] When people imagine a nucleus, many may think of a lumpy ball made up of protons and neutrons, Ayyad said. But nuclei can take on strange shapes, including what are known as halo nuclei.

Beryllium-11 is an example of a halo nuclei. It's a form, or isotope, of the element beryllium that has four protons and seven neutrons in its nucleus. It keeps 10 of those 11 nuclear particles in a tight central cluster. But one neutron floats far away from that core, loosely bound to the rest of the nucleus, kind of like the moon ringing around the Earth, Ayyad said.

[...] In 2019, the researchers launched an experiment at Canada's national particle accelerator facility, TRIUMF [...] It looked like the beryllium-11's loosely bound neutron was ejecting an electron like normal beta decay, yet the beryllium wasn't following the known decay path to boron.

The team hypothesized that the high probability of the decay could be explained if a state in boron-11 existed as a doorway to another decay, to beryllium-10 and a proton. For anyone keeping score, that meant the nucleus had once again become beryllium. Only now it had six neutrons instead of seven.

"This happens just because of the halo nucleus," Ayyad said. "It's a very exotic type of radioactivity. It was actually the first direct evidence of proton radioactivity from a neutron-rich nucleus."

[...] But science welcomes scrutiny and skepticism, and the team's 2019 report was met with a healthy dose of both. That "doorway" state in boron-11 did not seem compatible with most theoretical models. Without a solid theory that made sense of what the team saw, different experts interpreted the team's data differently and offered up other potential conclusions.

[...] "The work is getting a lot of attention. Wolfi will visit Spain in a few weeks to talk about this," Ayyad said.

Part of the excitement is because the team's work could provide a new case study for what are known as open quantum systems. It's an intimidating name, but the concept can be thought of like the old adage, "nothing exists in a vacuum."

[...] Open quantum systems are literally everywhere, but finding one that's tractable enough to learn something from is challenging, especially in matters of the nucleus. [...]

But this detective story is still in its early chapters. To complete the case, researchers still need more data, more evidence to make full sense of what they're seeing. That means Ayyad and Mittig are still doing what they do best and investigating.

Original Submission