Magnetic mirror concept -- electrons vs ions

[artis]

I am reading a book on fusion and just went over a paragraph of magnetic mirror confinement.

What I want to understand is this.
So all charged particles gyrate around magnetic field lines and if they have also a velocity parallel to the field they form helical paths. The gyroradius is directly proportional to B field strength and particle mass. So a higher field strength would result in smaller radius and lower mass would also result in smaller radius.

Now say we have an electron and a proton traveling at the same parallel velocity from a weaker B field towards a stronger one. The proton has a larger gyroradius while the electron has a smaller one. As the particles "climb up" the stronger B field their parallel velocities decrease and to compensate their perpendicular velocity increases (they start gyrating faster, spinning faster)
All in all the gyroradius of the electron will always be smaller in this case than that of the proton so does this mean that it is easier to confine protons/ions than electrons in a magnetic mirror?


thanks.

 

[mfb]

Now say we have an electron and a proton traveling at the same parallel velocity from a weaker B field towards a stronger one.

That would need the proton to have 2000 times as much energy. That's unlikely in a plasma. Better to assume the same energy for both.