Timeline for How are free electrons produced in a gas?
Current License: CC BY-SA 4.0
5 events
| when toggle format | what | by | license | comment | |
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| Jan 20, 2019 at 22:14 | comment | added | kkm mistrusts SE | Ah, that's fair. Perhaps I read the question to be more general. | |
| Jan 20, 2019 at 22:02 | comment | added | niels nielsen | I omitted the thermionics, even though I am a vacuum tube enthusiast, because I did not consider it relevant in the context of a discharge tube- which I took to be of the physics class demonstration variety. | |
| Jan 20, 2019 at 21:45 | comment | added | kkm mistrusts SE | I think it's fair to mention also (3) thermionic cathodes, probably the most common type used in lighting, where arc is started by preheating the electrodes. All T12/T8 lamps with 2 pins on each end are of this kind (opposed to CCFL). Also, CFL do operate in arc mode (dominated by thermal emission and ionisation, negative impedance), not glow mode (Townsend multiplication and secondary emission on non-thermal cathode, positive impedance). This is why the CFL use constant-current sources. See the graph in physics.stackexchange.com/q/116907/115253; point I is the glow-arc transition. | |
| Jan 19, 2019 at 7:39 | vote | accept | Mad Dawg | ||
| Jan 19, 2019 at 7:11 | history | answered | niels nielsen | CC BY-SA 4.0 |