Link between Green Glow and Electron

AI Thread Summary
The discussion centers on the green glow observed in electron diffraction patterns, primarily attributed to the impact of electron beams on phosphorescent screens. When electrons strike these screens, they excite atoms or molecules, which then emit light as they return to their ground state. The specific color emitted, such as green or blue, depends on the phosphorescent material used. Additionally, in cathode ray experiments, the light produced is due to the ionization of low-pressure gas within the apparatus. This phenomenon explains the observed green glow associated with electron beams.
harman90
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hi,
I just looking for Video on diffraction pattern of Electron, and noticed it produces green color pattern.
Earlier in chapter, when cathode ray was discovered, it was mentioned that Green glow was Noticed.

What is the reason for this green color?
 
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Do you mean when an electron beam strikes a phosphorescent screen? In that case, the electrons excite atoms or molecules in the screen upon impact. When those atoms or molecules relax to their ground state, they emit characteristic wavelengths of light which depend on the nature of the phosphorescent material. In the devices that I've used over the years, some have glowed green, others have glowed blue.
 
Hi, thank you very much for reply, I got it !
I again watched the video and Yes it is just the screen glowing ... Not the ray itself.

and I guess in cathode ray experiment, It contained gas at law pressure...! so light produced was due to ionization of gas.
Thank you again.
 
harman90 said:
and I guess in cathode ray experiment, It contained gas at law pressure...! so light produced was due to ionization of gas.
Thank you again.

That sounds likely.
 
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