Physicists say they have evidence for three never-before-seen combinations of quarks, just as the world's largest particle-smasher begins a new round of high-energy experiments.

The Standard Model, which describes the structure of atoms, is completely compatible with the three exotic particles.

Scientists hope that the current run of the LHC will turn up evidence of physics that goes beyond the standard model to explain dark matter. Evidence could point to a new array of particles in the universe.

The system of the LHC was upgraded for three years. Scientists and engineers at the research center on the French-Swiss border have been preparing for the restart of scientific operations since the shutdown ended in April.

The control center was a hive of activity as the data collection began.

The director-general of the European Organization for Nuclear Research said it was a magic moment. A new era of exploration has been opened by the fact that we just had a collision at an energy of 13.6 Tera-electronvolts.

During the previous two runs of the collider, the scientists collected as much data as they could. She said that this would increase our opportunities for discovery or understanding the fundamental laws of the universe.

During Run 3, the ring of magnets and detectors will be in use around the clock.

The start of the run comes 10 years after the biggest discovery to date: evidence for the existence of the Higgs boson, a particle that helps explain mass.

There are three new types of particles described during a seminar. They suggest that the universe's largest particle collider is on a quest to find more previously unseen building blocks.

Pentaquark illustration
A new type of pentaquark, shown as a pair of standard hadrons loosely bound in a molecule-like structure, is made up of a strange, charm and up quark, plus a down quark and a charm antiquark. Credit: CERN

Particles are smashed together at close to the speed of light to study hadrons, a type of quark.

The more analysis we do, the more exotic hadrons we find. The discovery of hadrons in the 1950s was followed by a quark model of hadrons in the 1960s. We are creating a new article.

Chris Parkes said that studying new combinations of quarks will help theorists understand the nature of exotic hadrons.

Most hadrons are ordinary. Three quarks are bound together to make up the particles. James Joyce wrote about three quarks for Muster Mark in his novel Finnegan's Wake. Two-quark combinations are called nywayanyday.

Four-quark and five-quark combinations are very rare and are thought to only exist for an instant.

Up and down, top and bottom, charm and strange are the six differentflavors of quaks. The team looked at the decays of negatively charged B mesons and found evidence for a pentaquark consisting of a charm quark and a charm antiquark. The first one to include a strange quark is this one.

Two new tetraquarks are illustrated here as single units of tightly bound quarks. One of the particles is composed of a charm quark, a strange antiquark and an up quark and a down antiquark (left), and the other is made up of a charm quark, a strange antiquark and an up antiquark and down quark (right). Credit: CERN

A charm quark, a strange antiquark, an up quark and a down antiquark are some of the quarks included in the two new tetraquarks.

There is an up antiquark and a down quark in the neutral one. This is the first time a pair of fourquarks have been observed together.

Exotic hadrons are seen as single units of tightly bound quarks. They are seen as pairs of standard hadrons that are bound together.

If the exotic hadrons are one, the other or both, it will only be a matter of time before we find out.

An illustration shows a pair of standard hadrons bound in a molecule.