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Name: Zackie R.
Status: student
Age: 13
Location: N/A
Country: N/A
Date: 2001-2002


Question:
When a proton or a neutron are not in a nucleus they die very quickly, so what happens to that dead particle? According to the laws of physics they just can't disappear.


Replies:
Zackie, The particles do not die. It is possible for particles to "decay" into other particles. One example is a neutron decaying into a set of three particles: a proton, an electron, a neutrino. It is possible for particles to join with other atoms. It is also possible for lone proton to join with an electron, thus becoming a hydrogen atom. A free proton or neutron does not disappear. It finds a way to become part of an atom or to change into different particles.

Dr. Ken Mellendorf
Illinois Central College


"Free" neutrons have a half life of ~12 min and decay by emission of a beta particle (electron), presumably yielding a proton. The energies can be found in any "Table of Neuclides" in any handbook of physics and / or chemistry. All the conservation laws are obeyed (energy/momentum/etc.), so there are no "dead" particles remaining. The proton, and the deuteron both are stable, at least on any time scale less than "cosmic".

The mass ~3 isotope tritium has a half life of about 12 years.

None of the particles disappear.

Vince Calder


Protons outside of nuclei have not been observed to do anything. They just stay on being protons. A neutron by itself can "decay" into a neutron, a positron, and an antineutrino. Nothing disappears, it just isn't a neutron any more.

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



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