ABCs
of
particle
physics
is for accelerator, which makes things move fast.
Accelerators take tiny particles and speed them up. They can smash particles into a piece of matter or make two particles collide head on. They are in operation around the world, serving medicine, industry, energy, the environment, national security, and discovery science. In particle physics research, scientists use accelerators to discover new particles and explore how the universe works.
A
Black holes are extremely dense, with so much gravity that even light cannot escape them. Within a black hole, the known laws of physics go out the window. Scientists think there could be around 100 million black holes within the Milky Way galaxy and estimate billions upon billions more in the universe.
is for black holes,
they have lots of mass.
B
A cryostat is an apparatus that keeps things very cold. Many pieces of particle physics experiments work only when they’re chilled to very low temperatures, as little as a few degrees above absolute zero. Cryostats keep superconducting materials cold enough to conduct electricity without resistance, and they can keep particle detectors cold enough to register even the most miniscule deposits of energy from particles such as dark matter.
is for cryostat,
so icy and cold!
C
D
is for detector, where collisions unfold.
Particle detectors are scientists’ windows to the subatomic world. When a particle hits a detector, it gives up information such as its energy, direction, speed and electric charge. Detectors are often made up of multiple layers and devices to measure these different aspects of the particles they study and to figure out the identity of the particles they detect.
E
is for energy, which must be conserved.
Energy comes in many forms, and the total amount of energy in a reaction is always conserved–which is great news for particle physicists. By measuring the energy that comes out of particle collisions, scientists can determine whether it is equal to the energy that went into them. If it’s not, some of that energy might have been carried away by something hard to detect, such as a neutrino.
F
We’re most familiar with the force of gravity, which holds us on the Earth and makes us circle the sun. But at the smallest scales gravity is weak, and particles interact with much stronger forces. There is the strong nuclear force, which holds the nucleus of atoms together; the weak nuclear force, which allows particles to decay; and the electromagnetic force, which holds atoms and molecules together.
is for forces,
making particles swerve!