Scientists have proposed a new kind of subatomic particle to explain another particle’s mysterious disintegration. The kaon, a special case of meson particle, is made of one quark and one antiquark.

Everything we see around us, from the ground beneath our feet to the most remote galaxies, is made of matter. For scientists, that has long posed a problem: According to physicists’ best current ...

Two independent lines of evidence from the world’s most powerful particle experiments are converging on the same uncomfortable conclusion: something is producing signals that the Standard Model of ...

Scientists are on the trail of a mysterious five-particle structure that could challenge one of the biggest theories in physics: string theory. This rare particle—never seen before and predicted not ...

When you throw a ball in the air, the equations of classical physics will tell you exactly what path the ball will take as it falls, and when and where it will land. But if you were to squeeze that ...

Scientists at Fermilab’s MicroBooNE experiment have ruled out the existence of the elusive sterile neutrino, a particle proposed for decades to explain puzzling neutrino behavior. Their high-precision ...