What causes the rings in the electron motion video?

[Drakkith]

The video here: http://www.youtube.com/watch?v=IPdO-NIUuEo&feature=related
shows an electron in motion and I had a few questions about it.

1. Are the "rings" that make it up caused because of interference between the photons and the electron?
2. Is that the reason why the center is completely black?
3. Do these photons have any effect on the electron, such as interfering with its motion?
4. Are they bouncing off of the electron, or "passing through" it to be detected?

Thanks all.

 

[chrisbaird]

The original article is http://prl.aps.org/abstract/PRL/v100/i7/e073003" .

I believe they created each image in the movie by adding together a bunch of images. When electrons are detected, they are detected as particles, which means just one pixel lights up in the image. But by imaging many electrons and adding up the images, a more extended pattern emerges. It is like doing a double-slit experiment and building an interference pattern up by registering a large number of electron hits. The importance of this particular work is that the imaging system is very fast, which means that the final image is not just a picture of an interference pattern, but can by thought of as a picture of the electron's wave itself.

1. The "rings" are the electron. Bound electrons exist in localized wave shapes independent of anything a photon does to it. The photons where used to excite the electrons so they could be imaged.

2. The center is black because that is the wave shape of this particular electron configuration.

3. The photons were used to speed up the electrons

4. I believe the electrons are absorbing the photons and that is why the speed up.

 

[Drakkith]

Ah, I understand a bit more now. Thanks!