Mystery of dark matter may be solved after discovery of ‘exciting’ new particle, UK scientists say

Mysterious and invisible, dark matter is believed to be all around us and is estimated to make up 85 per cent of all matter in the universe. But why can’t we find it?

Scientists are sure it exists because without the extra matter the movements and gravitational interactions of galaxies and stars make no sense.

But despite decades of study and numerous different theories and tests to find its origin, it has remained a shadowy enigma.

Now, nuclear physicists at the University of York have identified an “exciting” new particle which they are putting forward as a candidate to explain the formation of dark matter.

They have named the new particle the “d-star hexaquark”.

The particle is composed of six quarks – the fundamental particles that usually combine in trios to make up protons and neutrons – the basis for atoms and matter as we currently know it.

But the team found that the six quarks in a d-star result in a boson particle, which means that when many d-stars are present they can combine together in very different ways to the usual protons and neutrons.

Bosons are particles which obey Bose-Einstein statistics – a theory which describes how particles interact and can form a “fifth state of matter”, known as Bose-Einstein condensate.

The research group at York suggest that in the conditions shortly after the Big Bang, many d-star hexaquarks could have grouped together as the universe cooled and expanded, and formed this condensate.

Dr Mikhail Bashkanov and Professor Daniel Watts from the department of physics at the University of York recently published the first assessment of the viability of this new dark matter candidate.

Professor Watts said: “The origin of dark matter in the universe is one of the biggest questions in science and one that, until now, has drawn a blank.

“Our first calculations indicate that condensates of d-stars are a feasible new candidate for dark matter. This new result is particularly exciting since it doesn’t require any concepts that are new to physics.”

Co-author of the paper Dr Bashkanov said: “The next step to establish this new dark matter candidate will be to obtain a better understanding of how the d-stars interact: when do they attract and when do they repel each other?

“We are leading new measurements to create d-stars inside an atomic nucleus and see if their properties are different to when they are in free space.”

The research team at York will now collaborate with scientists in Germany and the US to test their theory of dark matter and search for d-star hexaquarks in the cosmos.

A New Possibility for Light-Quark Dark Matter is published in the Journal of Physics G Letters.