How does Muon g-2 work?

A beam of muons with aligned spins is directed into a storage ring that has a very precisely known magnetic field. As the beam goes around this storage ring, the muons’ spins wobble, or precess. The magnitude of that precession is directly related to the difference of g from 2, or g-2.

What does a muon do?

Muons can help detect dangerous nuclear material and see into damaged nuclear power plants. Scientists use muons for archeological purposes to peer inside large, dense objects such as the pyramids in Egypt.

Why was the storage ring moved from Brookhaven Lab to Fermilab?

Credit: Fermilab. The Muon g-2 storage ring, in its current location at Brookhaven National Laboratory in New York. The ring, which will capture muons in a magnetic field, must be transported in one piece, and moved flat to avoid undue pressure on the superconducting cable inside.

Does Fermilab have a particle accelerator?

As America’s particle physics laboratory, Fermilab operates and builds powerful particle accelerators for investigating the smallest things human beings have ever observed. About 2,300 physicists from all over the world come to Fermilab to conduct experiments using particle accelerators.

What can wobbling muons tell us?

Like electrons, muons are magnetic. When measuring the magnetic strength of any particle, scientists put it near a magnet in a magnetic field, and then measure the direction of a muon’s wobble. A faster wobble means a stronger magnetism.

How do scientists measure particles?

Particle positions can be measured by the silicon vertex detector. Which is basically a collection of PN junction diodes. (4) Velocity or momentum also can be measured by a gas chamber in the presence of a magnetic field.

What is special about the muon?

Muons have the same negative charge as electrons but 200 times the mass. They are made when high-energy particles called cosmic rays slam into atoms in Earth’s atmosphere. Travelling at close to the speed of light, muons shower Earth from all angles.

What is the muon g-2?

In a seminar on Wednesday, researchers with Fermilab in Batavia, Illinois, announced the first results of the Muon g-2 experiment, which since 2018 has measured a particle called the muon, a heavier sibling of the electron that was discovered in the 1930s.

How does Fermilab’s muon g-2 compare to the Large Hadron Collider?

Unlike the LHC, which smashes particles together to make new kinds of particles, Fermilab’s Muon g-2 experiment measures known particles to extreme precision, searching for subtle deviations from Standard Model theory. “The LHC, if you like, is almost like smashing two Swiss watches into each other at high speed.

What can we learn from Fermilab’s m3?

For example, Krnjaic helped propose a Fermilab program called M3 that could narrow the possibilities by firing a beam of muons at a metal target—measuring the energy before and after the muons hit. Those results could indicate the presence of a new particle.

Why study the muon?

Studying the muon is “almost the most inclusive probe of new physics,” says Muon g-2 team member Dominik Stöckinger, a theorist at Germany’s Dresden University of Technology. The Muon g-2 experiment starts with a beam of muons, which scientists make by smashing pairs of protons together and then carefully filtering through the subatomic debris.