Quarkonium facts for kids

Quarkonium (say: kwark-OH-nee-um) is a special kind of tiny particle. Imagine a very small building block of matter. Quarkonium is made of two of these building blocks: a heavy quark and its matching antiquark.

Think of a quark as a type of fundamental particle. An antiquark is like its opposite twin. When a heavy quark and its own antiquark join together, they form quarkonium. This particle is "neutral," meaning it has no electric charge. It's also its own "antiparticle," which is pretty cool!

What Are Quarks?

Quarks are some of the smallest particles we know. They are like the tiny pieces that make up bigger particles such as protons and neutrons. Scientists believe there are six different types, or "flavors," of quarks.

These flavors are:

• Up
• Down
• Charm
• Strange
• Top
• Bottom

Quarks are always found in groups. They are never alone. Protons and neutrons, for example, are made of three quarks.

What Is an Antiquark?

Every particle in the universe has an "antiparticle." An antiparticle is like a mirror image of a particle. It has the same mass but opposite properties, like electric charge.

So, an antiquark is the antiparticle of a quark. For example, an "up quark" has an "anti-up quark." When a particle meets its antiparticle, they can destroy each other in a burst of energy!

How Is Quarkonium Formed?

Quarkonium is special because it's made of a heavy quark and its own antiquark. The "heavy" quarks are the charm quark, bottom quark, and top quark.

When a charm quark joins with an anti-charm quark, they form a type of quarkonium called charmonium. When a bottom quark joins with an anti-bottom quark, they form bottomonium. When a top quark joins with an anti-top quark, they form toponium.

These particles are very unstable and exist for only a tiny fraction of a second before changing into other particles.

Why Is Quarkonium Important?

Scientists study quarkonium to learn more about the strong force. This is one of the four basic forces of nature. It holds quarks together inside particles.

By studying how quarkonium forms and breaks apart, scientists can better understand how the strong force works. This helps us learn more about the basic building blocks of our universe.

Images for kids

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  Bottomonium is made of a bottom quark and an anti-bottom quark.

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  Toponium is made of a top quark and an anti-top quark.

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