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Name:  Malini
Status:  student
Age:  18
Location: N/A
Country: N/A
Date: 2000-2001

Can beta particles cause ionization of the media they pass through?

Yes. Alpha, beta, gamma, X, and energetic neutron radiation are all ionizing.

Richard E. Barrans Jr., Ph.D.
Assistant Director
PG Research Foundation, Darien, Illinois


Yes, beta particles can cause ionization. There is a very simple reason for this: beta particles are electrons. When first discovered, it was not known what beta radiation was. Then it was discovered that beta radiation is negatively charged particles. Later, specific charge and mass were identified. They are electrons.

Beta radiation is a neutron breaking up to a proton, an electron, and a neutrino. The neutrino doesn't do much: a neutral particle that can pass through the entire Earth without interacting. The proton tends to remain within the atom. The electron has enough energy to exit the atom, often exiting the entire piece of radioactive material.

An electron can join onto another atom, temporarily making it a negative ion. It can knock another electron free from an atom, making it a positive ion. It can also join with a proton to form a neutron (beta decay in reverse), making a negative ion. Regardless of how it happens, there are enough particles flying through the air to eventually de-ionize any ion.

Dr. Ken Mellendorf

Yes, if they are going fast enough.

Tim Mooney

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