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an antimatter particle with the same mass as an electron but with a positive charge

For instance, a positron is an antimatter particle with the same mass as an electron but with a positive charge.

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a sub-nuclear particle with the same mass as an electron but with a positive charge

A positron is a sub-nuclear particle with the same mass as an electron but with a positive charge.

both directions the antimatter counterpart of the electron

And when the electron is moving backwards in time both directions is a positron; the antimatter counterpart of the electron.

an antimatter particle which is similar to an electron but has a positive charge

A positron is an antimatter particle which is similar to an electron but has a positive charge.

an elementary particle of antimatter

A positron is an elementary particle of antimatter.

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a particle that has the same mass as an electron but carries a positive charge

A positron is a particle that has the same mass as an electron but carries a positive charge.

the positively charged antimatter counterpart to the electron

(A positron is the positively charged antimatter counterpart to the electron.)

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a particle exactly like an electron, but with an opposite, positive charge

A positron is a particle exactly like an electron, but with an opposite, positive charge.

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the anti-particle for an electron (a particle with a negative charge

For example, the anti-particle for an electron (a particle with a negative charge) is a positron.

a subatomic particle with the same mass as an electron and a numerically equal but positive charge

A positron is a subatomic particle with the same mass as an electron and a numerically equal but positive charge.

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