Mm.. actually I think Beam Cannons are more or less feasibly possible. Technically all lasers cannons are beam cannons, yet you are not likely to see them. However a particle cannon
practically doesn't give a crap what color it is depends on what you use in it for its color, I think, so I simply assume all beam cannons in FS are a form of really advanced high powered particle cannon that can be sustained for a really long time.
I really do believe that humanity may see particle beams used as weapons in the future.. but none of us personally will see it

As for a low-energy example of a Particle Beam, look at any activated cathode ray tube.
As for Blob cannons...

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