Definition

Noun: - The emission of electrons from a surface that is bombarded by higher energy primary electrons: A physical phenomenon where a material, when struck by a beam of energetic particles (primary electrons), releases its own electrons.

Usage

• This term is used primarily in physics and engineering contexts to describe a specific electron emission process.
• It is often discussed in relation to the operation of devices like photomultiplier tubes, certain types of vacuum tubes, and in surface science.

Examples

• Noun:
  • The efficiency of the photomultiplier tube depends on the secondary emission from its dynodes.
  • Scientists studied the secondary emission from the metal surface to understand its electronic properties.

Advanced Usage

• "Secondary emission coefficient": A key parameter representing the average number of secondary electrons emitted per incident primary electron.
  • A material with a high secondary emission coefficient is chosen for the dynode.
• "Secondary emission yield": Essentially synonymous with the secondary emission coefficient, describing the ratio of emitted secondary electrons to incident primary electrons.

Variants and Related Words

• Secondary electron (n): An electron emitted via the process of secondary emission.
  • The detector collects the secondary electrons to form an image.
• Primary electron (n): The initial, higher-energy electron that causes secondary emission upon impact.
  • The beam of primary electrons is focused onto the sample.

Synonyms

• Secondary electron emission: A more explicit, full-term synonym.

Related Phrases

• To result from secondary emission: To be caused by this process.
  • The amplified signal results from secondary emission within the tube.
• To exhibit secondary emission: To show or demonstrate this property.
  • The coated surface exhibits strong secondary emission.

Notes

• "Secondary emission" is a compound noun where "secondary" modifies "emission" to specify the type. The core concept explained is the entire phrase.
• It is distinct from thermionic emission (electron emission due to heat) and photoelectric emission (electron emission due to light).

Noun

1. the emission of electrons from a surface that is bombarded by higher energy primary electrons