Spin states Physicists could soon be putting the Standard Model to the test by observing transitions in a one-positron quantum cyclotron. (Courtesy: Shutterstock/Inna Bigun)"> Spin states Physicists could soon be putting the Standard Model to the test by observing transitions in a one-positron quantum cyclotron. (Courtesy: Shutterstock/Inna Bigun)

For the first time, physicists in the US have trapped a single positron such that its lowest-energy quantum states can be fully resolved. Gerald Gabrielse and colleagues at Northwestern University did this by creating a device that they call a “one-positron quantum cyclotron”. The team hopes that future studies could measure the positron’s magnetic moment with unprecedented precision. This could pave the way for the an extremely stringent test of a fundamental symmetry of the Standard Model of particle physics.

The Standard Model has been extraordinarily successful at describing fundamental particles and how they interact with each other.…