Has a stationary electron ever been seen/detected?

Question

the title says it all. i mean, no electron was trapped in a magnetic field and observed for example. i know latley using a TEM on a graphene, impurity atoms can be seen using false colour. have electrons been trapped or slowed down significantly, or the elctrons we know are all orbital and from guns?

thanks

Answer 1

maybe at absolute zero cold

Answer 2

You may trap electrons in a Penning trap for example. A synchrotron may be considered a 'trap' in the sense that it allows storage of electrons.

Detection of single electrons works by capturing the electron in a particle detector or tracing its path in a bubble-chamber, for example.

I guess you are interested in 'seeing' single SLOW electrons. This is quite difficult. I can only speculate about a possibility: have an electron in a trap with different energy levels for the electron and induce/observe transitions between the energy levels with lasers etc. Or kick out an electron of a trap with photons (e.g. X-ray) and observe compton scattering.

Also, the annihilation of an electron and a positron can be observed easily using gamma detectors.

You cannot use conventional TEM for such light particles as electrons. However there are electron-electron scattering experiments. These are done at high energies (fast electrons) rather than trapped electrons, usually.

Answer 3

You can't hold an electron in a magnetic field. You can influence it's movement, but it has to be moving.

You could hold one in an electric balance like in Millikans Oil Drop experiment, but without the oil drops.

But as soon as you shine a light at the electron to look at it, it will skip away.

This might something to do with Hizenburg, but I'm not sure.