The last time I asked you guys what the difference between Ions and plasma was I believe it was essentially said that ions are megnetically accelerated and contain less energy hower plasma is extremely hot and contains a lot of energy... So what if you electromagnetically accelerate plasma particles? I just used what I was told here to come up with an idea.
I wish sci fi shows didn't throw scientific terms around like "ion," "plasma," and others quite so much.
There is nothing special about an ion. It is a particle that has a positive or negative charge (thus it attracts oppositely charged particles and repels like charges). There are trillions upon trillions of ions around you at all times.
Pour some table salt into a cup of water and let it dissolve. Congratulations, you now have Na+ and Cl- ions in the solution in the cup.
It is true that electromagnetic fields can be used to change the speed or direction of ions. This is kinda the principle upon which a particle accelerator works.
A plasma is an ionized gas (gas made up of ions), or one containing free electrons. It doesn't need to be high temperature (we can thank high school chemistry and physics classes for giving people the bad idea that plasma is the "4th state of matter" beyond the gas phase), although plasmas are typically formed by heating (heat provides enough energy to cause the atoms in the gas to ionize).
Plasmas are present inside of fluorescent tubes, camera flash tubes, and other kinds of gas discharge tubes (like neon lights). Electric arcs also provide sufficient energy to ionize the air where the arc occurs, so plasmas exist there.
As you can see this doesn't imply extreme temperatures necessarily (a fluorescent or neon tube generally doesn't get to 10,000 degrees F).
Now, you mention accelerating ions to make some kind of weapon. Interesting idea, but this isn't that feasible for a few reasons:
1. You need a huge amount of energy to be able to produce an electromagnetic force to accelerate the ions to the great speed that would be needed to do any damage.
2. You would need a LOT of ions. (The mass of one atom is so tiny, that you hardly do any damage with one alone).
3. To get up to the speed needed would require multiple acceleration "stages" to get up to the speed required (there's a reason particle accelerators are many miles long).
Basically it sounds like you are trying to kill tanks with a tube from a TV set (a very similar principle is at work here -- electrons are emitted from the cathode inside the tube, they are accelerated and deflected (aimed) using electromagnetic coils wrapped around the neck of the tube, and hit the phosphors on the screen, causing them to glow). Scaling this idea up to a vehicle turret doesn't seem like it'd be very effective.