Differences in Semiconductor Soft Errors Caused by Cosmic-Ray Muons and Neutrons

Re:Differences in Semiconductor Soft Errors Caused by Cosmic... by tooltower on Monday July 26, 2021 @07:16AM (#27958060)

From the article, what's a "thermal neutron beam"?

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Re:Differences in Semiconductor Soft Errors Caused by Cosmic... by adrian_b on Monday July 26, 2021 @08:45AM (#27958687)

Thermal neutrons are slow neutrons, which have a velocity and kinetic energy similar to those of atoms that are in thermal equilibrium at the ambient temperatures.

When the neutrons are generated in nuclear reactions, they have a very high kinetic energy, but after many collisions with the matter encountered in their path, they lose most of the energy.

After they have become slow enough, so that the likelihoods of losing or gaining energy in collisions become similar, they are considered thermal neutrons.

So a "young" neutron is a fast neutron, after some time it becomes a thermal neutron and eventually it decays into a hydrogen nucleus (proton).

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Re:Differences in Semiconductor Soft Errors Caused by Cosmic... by baq on Monday July 26, 2021 @08:10AM (#27958441)

https://en.wikipedia.org/wiki/Neutron_temperature

    0.025 eV  Thermal neutrons

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Re:Differences in Semiconductor Soft Errors Caused by Cosmic... by caf on Monday July 26, 2021 @08:30AM (#27958581)

It's neutrons with kinetic energy that's similar to the other particles in the environment, so they're at thermal equilibrium.

Read it as "low energy neutrons".

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Re:Differences in Semiconductor Soft Errors Caused by Cosmic... by Sharlin on Tuesday July 27, 2021 @05:32AM (#27970414)

Thermalizing neutrons is also what the moderator (typically water but can also be eg. graphite, like in the infamous RBMK reactor design) surrounding the fuel rods in a nuclear reactor is for. Neutrons fresh from a fission reaction are too fast to reliably induce additional fissions before escaping and being absorbed by the reactor walls.

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Re:Differences in Semiconductor Soft Errors Caused by Cosmic... by tobmlt on Monday July 26, 2021 @11:29AM (#27960646)

Since others have answered, for contrast high energy is sometimes denoted “ultraviolet” also high energy “hard” vs low energy “soft” loosely speaking

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Re:Differences in Semiconductor Soft Errors Caused by Cosmic... by TrumpsHandler on Monday July 26, 2021 @07:46AM (#27958270)

Probably neutrons that are slowed enough/have lost sufficient energy to break atoms or be absorbed into an atom.

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