An example of something considered to be "slow" is the muon. You could kind of thinking of it as a heavy electron (though that hand waves away a lot). It has a mean lifetime of 2.2 μs - which is fairly slow.
Also note that they're not rare and there's a fair bit of neat science behind that too.
> About 10,000 muons reach every square meter of the earth's surface a minute
There's also neat stuff with time dilation and muons ( http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/muon.html ) - there should be far fewer observed muons at the surface if muons didn't experience time dilation from their relativistic speeds.
> The historical experiment upon which the model muon experiment is based was performed by Rossi and Hall in 1941. They measured the flux of muons at a location on Mt Washington in New Hampshire at about 2000 m altitude and also at the base of the mountain. They found the ratio of the muon flux was 1.4, whereas the ratio should have been about 22 even if the muons were traveling at the speed of light, using the muon half-life of 1.56 microseconds. When the time dilation relationship was applied, the result could be explained if the muons were traveling at 0.994 c.
(note: mean lifetime and half-life are different numbers)
The thing here is that 2.2 μs is slow, but even with something that is that fast (on a human scale), there's a lot of neat science that can be done with them. They've even made muonic atoms (where the electron is replaced by a muon) https://en.wikipedia.org/wiki/Exotic_atom ... and that leads to possibilities on lowering fusion temperature ( https://en.wikipedia.org/wiki/Muon-catalyzed_fusion ) because the muon is much closer to the nucleus in its ground state.
Also note that they're not rare and there's a fair bit of neat science behind that too.
> About 10,000 muons reach every square meter of the earth's surface a minute
(from https://www.scientificamerican.com/article/muons-for-peace/ ).
There's also neat stuff with time dilation and muons ( http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/muon.html ) - there should be far fewer observed muons at the surface if muons didn't experience time dilation from their relativistic speeds.
> The historical experiment upon which the model muon experiment is based was performed by Rossi and Hall in 1941. They measured the flux of muons at a location on Mt Washington in New Hampshire at about 2000 m altitude and also at the base of the mountain. They found the ratio of the muon flux was 1.4, whereas the ratio should have been about 22 even if the muons were traveling at the speed of light, using the muon half-life of 1.56 microseconds. When the time dilation relationship was applied, the result could be explained if the muons were traveling at 0.994 c.
(note: mean lifetime and half-life are different numbers)
The thing here is that 2.2 μs is slow, but even with something that is that fast (on a human scale), there's a lot of neat science that can be done with them. They've even made muonic atoms (where the electron is replaced by a muon) https://en.wikipedia.org/wiki/Exotic_atom ... and that leads to possibilities on lowering fusion temperature ( https://en.wikipedia.org/wiki/Muon-catalyzed_fusion ) because the muon is much closer to the nucleus in its ground state.