muons

The muons have much more mass than the electrons, so the radius of the orbit is much smaller.

The challenge is that muons are highly unstable and decay in microseconds, requiring rapid acceleration.

They look similar and have the same mass (whatever that means), but they are very different, for example only the left-handed muons feel the weak force.

You can do the same with other particles, for example for muons g=2.0023318414, because the corrections are slightly different.

They are basically doing a cat scan of a large object using natural muons, cosmic rays.

(page 4 is muons on Copper) But again, I think your doubts about the numbers is certainly warranted.

A pity muons are so expensive to generate, since at method is theoretically and effectively beautiful.

The main difference is that electrons are readily available while muons have to be created.

These beams are then rather wider and harder to handle, as muons decay quite quickly.

These interactions produce pions and kaons, which decays further until you end up with a bunch of electrons/positrons, gamma rays, and muons.

That's one reason physicist are considering using Muons in future accelerators instead of protons.

Then you have to capture the muons into orbits around protons that come from hydrogen that needs to be disassociated and ionised.

The muon flux at sea level is about 1 per cm 2 per second, or 36 million per m 2 per hour, or 360 hits per hour on a camera target, so even granted that the "active" area of the target is only a few percent of the physical area, muons more than account for the signal he is seeing, and muons deposit a lot of energy.

If you're going to ask for "direct evidence" you need to be extremely clear what you mean, and your definition really should be such that the evidence we have for the existence of neutrons or muons counts as "direct".

[…] Since 2010s researchers are also exploring and attempting to use artificially generated muons—created by conventional accelerators or laser-plasma systems—for muon tomography.” I may overlook something, but skimming the references, I get the impression the latter still is an idea.

Muons are not stable, thus you cannot tear them off matter as you'd do with electrons.

Muons are elementary particles like electrons but are 200 times heavier, allowing for high-energy, clean collisions.

Muons are good because they are easy to identify, then you look back at where they came from and see what other things were created.