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Glite Dictionary
delta ray

delta ray

9.9
A fast electron knocked out of an atom when radiation hits it
  • noun
  • /ˈdɛltə reɪ/
  • Specialized
translation icon : rayo delta
  • During the experiment, the scientists measured the energy of the emitted delta rays from the irradiated samples.

Examples

  • The particle detector recorded several delta rays that were produced during the ionization process.

  • Powering up the delta ray scanners.

    Wheely (2018)

  • Researchers observed a burst of delta rays when the radioactive material was exposed to high-energy particles.

Surface Forms

delta ray singular
delta rays plural

Morphology

delta + ray

The specialized physics sense 'a high-speed secondary electron' is not transparently derivable from the constituents: 'ray' suggests a beam but 'delta' (a Greek letter or marker for change) gives no clear clue to an electron. This is a domain-specific technical term whose meaning is idiomatic within physics, so a B1 learner who knows the words would not reliably infer the MWE meaning.

Etymology

Delta ray may come from the picture scientists saw: tiny electrons that 'branch off' the main particle path like streams in a river delta, forming little rays from the track. That's why it means 'a small electron thrown off by a passing particle'.