Townsend discharge
Electron multiplication cascade
A Townsend discharge is the initial stage of electrical breakdown in a gas, where free electrons collide with gas molecules and release more electrons in a cascading process called electron avalanche.
Named after physicist John Townsend, this phenomenon explains how gases transition from insulators to conductors under sufficient voltage: The neon sign operates through a controlled Townsend discharge.
mechanism
Multiplicative ionization cascade
- secondary emissionParticles released by impact
- multiplicationProduct-finding operation
- spark gapSpace for electrical discharge
- self-sustainingAble to continue independently
electron avalanche
Multiplicative ionization cascade
- secondary emissionParticles released by impact
- multiplicationProduct-finding operation
- spark gapSpace for electrical discharge
vacuum chamber
Enclosure with removed atmosphere
- Geiger counterIonizing radiation detector
gas pressure
Force exerted by gas
- Electrical Dischargesarc, spark, lightning, corona, electric arc
- electrical dischargespark, arc, corona, plasma, lightning
- glow dischargestriations
- ionizationion, ionization, ionizer, anion, photoionization