ALPHA Collaboration facts for kids

The ALPHA Collaboration is a team of scientists from about 11 universities. They work together to try and trap neutral antimatter. They are trying to trap a special type of antimatter called antihydrogen. Antihydrogen is like the opposite version of hydrogen. Hydrogen is the simplest atom on the periodic table.

Both hydrogen and antihydrogen have two particles with opposite electric charges. Hydrogen has a proton (positive charge) and an electron (negative charge). Antihydrogen has an antiproton (negative charge) and a positron (positive charge). A positron is also known as an antielectron.

Where ALPHA Works

The ALPHA Collaboration has its experiment at CERN. CERN is a large science lab located in Geneva, Switzerland. It is the only place in the world that can create "slow" antiprotons. These slow antiprotons are easier for ALPHA to capture.

ALPHA then brings these antiprotons together with positrons. When they meet, they form antihydrogen.

Trapping Antihydrogen

Antihydrogen, like many atoms, acts a bit like a tiny magnet. Scientists call this a magnetic dipole moment. Normally, small magnets are attracted to other magnets. However, some atoms can be pushed away by magnetic fields.

This means these atoms can be held in place by creating a special magnetic field. ALPHA is trying to do this with antihydrogen. They use a clever setup of magnets to create a "magnetic minimum trap." This trap can hold antihydrogen atoms in space.

Trapping antihydrogen is very difficult. The magnetic forces that hold these atoms are quite weak. This means the trap can only hold antihydrogen atoms that are moving very slowly. Atoms that move slowly are also very cold.

The ALPHA trap can hold antihydrogen atoms if they are colder than about 0.5 Kelvin. This is just 0.5 degrees above absolute zero, which is extremely cold! ALPHA is currently working on making antihydrogen this cold.

Images for kids

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  CERN's AD with the ALPHA, ASACUSA and ATRAP collaborations.

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  ELENA ring

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  ALPHA experiment

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  CERN Antimatter factory – GBAR (Gravitational Behaviour of Anti hydrogen at Rest) experiment

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  Official BASE logo

See Also

Antiproton Decelerator#ALPHA collaboration