1 / 10

Particle acceleration by electric field in an 3D RCS

This study analyzes the motion of particles in a 3D RCS under the influence of electric and magnetic fields. The particle trajectories and energy spectra are examined, revealing electron and proton acceleration and precipitation. The results suggest a scheme for proton/electron acceleration and precipitation.

eknapp
Download Presentation

Particle acceleration by electric field in an 3D RCS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Particle acceleration by electric field in an 3D RCS Valentina Zharkova and Mykola Gordovskyy

  2. Magnetic field topology - Case 2, By =const (Zh&G, MNRAS, 2005) Bz = B0 tanh( - x/d) Bx = B0 (z/a) By = +/- By0 = 0.0001Tl B0 = 0.01Tl Ey0 = B0Vinflow – 1/μ dBz/dx Vinflow 0.01 Valfven  104m/s Ey0 = 100V/m

  3. General analysis of the particle motion: trajectories • Electric field is the force that governs a straightforward movement of accelerated particles along the Y-axis, so for a particle with the charge q the Y-component will have a velocity Vy Vy q/m Ey • Obeying the X-component of magnetic field, by Lorenz force, particle is rotated through the angle of ~90o before being ejected with: Vz q/m Vy Bx = q2/m2 Ey Bx2 • The particle velocity Vxoccurring owing to a gyration is defined by the Y-component of magnetic field and the Z-component of a particle velocity as follows: Vx q/m Vz By q3/m3 Ey Bx By3 • Hence, Vx is positive for electrons and negative for protons, if By>0, and vice versa if By < 0.

  4. Electron trajectories By > 0 By < 0

  5. Asymmetry rateAR=[Np+ -Np-) – (Ne+ -Ne-) ]/ [Np+ -Np-) + (N + -Ne-)]

  6. Particle trajectories – case 2 (E~ Bx-2 ~z-2)blue – RCS edge, green – close to X-point

  7. Energy spectra:protons (left) and electrons (right)By=10-4T (solid)vs By=10-2T (dashed) εe~C1 Ey√ ( 1 + By2/Bx2) Eelow~ A Ey √ (1 + By/B0)2) εp~CEy2 /Bx2√(1 +By/B0) Eplow ~ Ey2/B02 √(1 +By/B0)

  8. Energy spectra: e (blue) and p (black)upper panel – neutral, middle – semi-neutral,lower – fully separated beams 1.8 for p 2.2 for e 1.8 for p 2.2 for e 1.7 for p 4-5 for e 4-5 for p 2.0 for e 1.5 for p 1.8 for e

  9. Proton beam compensated by proton-energised electrons precipitate about 10s Pure electron beams, compensated by return current, precipitate in 1s The suggested scheme of proton/electron acceleration and precipitation

More Related