⚛️ Nucleus breaking 🪨 Fragments ejected

spallation

1 9.9

The central part of an atom breaks into smaller pieces when a fast particle hits it

noun
/spəˈleɪʃən/

Specialized

: espalación

There are two types of thermal neutron sources: nuclear reactors, which produce neutrons during the fission of enriched uranium, and spallation sources, which produce neutrons when accelerated protons smash into a metal target.
spallation source
spallation neutrons

Examples

Because spallation neutrons are produced by an accelerator, they can be timed and their wavelengths determined.

Academic text (2003)
Krebs also had a hand in the development of the $1.3 billion Spallation Neutron Source at Oak Ridge.

Academic text (1999)
But I do look forward to nuclear power that does not rely on fission, other than spallation of lithium.

Blog text (11)
The Europeans do not plan another reactor source but currently hope to build a 5-MW spallation source.

Academic text (1994)
The Kohn panel included researchers involved with both spallation sources and research reactors.

Academic text (1994)
Moreover, spallation sources are usually pulsed, so they are more suitable, say, for time-of-flight measurements than for isotope production.

Academic text (1994)
In 1985, England built a spallation source, Isis, at the Rutherford Appleton Laboratory in Chilton.

Academic text (1994)
Congress and DOE are concerned about the progress in building the $1.3 billion Spallation Neutron Source (SNS) at Oak Ridge National Laboratory in Tennessee.

Academic text (1999)
To approach the same time-averaged flux as the ANS would require an equally costly 5-MW spallation source, which, in the panel's opinion, is still far off on the technological frontier.

Academic text (1994)
The process of spallation is crucial in certain nuclear reactions where a nucleus is broken apart by high-energy particles.

Surface Forms

spallation singular

spallations plural

Morphology

spallation = spall (semi-transparent) = spall + ation

Formed as a standard nominalization of 'spall', but the nuclear-physics sense is a specialized technical application that may not be obvious to general learners.

Etymology

Spallation comes from the verb spall, which means 'to break off into small pieces', so imagine a nucleus hit and sending tiny bits flying. So in nuclear science spallation is when a nucleus struck by a fast particle breaks up into several smaller pieces.