METHOD TO PRODUCE HIGH-CHARGE ION BEAM Russian patent published in 2012 - IPC H01J27/18 

FIELD: electricity.

SUBSTANCE: intense pulse flow of heavy ions in this method is developed by multiple ionisation of heave ions in a rotary electronic ring, electrons in which are of high density and are retained for a long period of time along radius with a combination of a homogeneous H_z=560 Gs and multiple H_m=830 Gs magnetic fields. Retention of electrons in a trap in longitudinal direction is carried out by a field of two turns with current arranged at the ends of the trap, which develop a radial magnetic field H_r with intensity H_r=300 Gs. Injection of electrons with energy W_e=105 keV is carried out to an equilibrium radius r_a=2 cm. in the area of the left turn. Longitudinal speed of electrons in injection is V_z=3*10⁹ cm/s, capture of electrons into the trap is carried out by quick (for the time less than half-cycle of electron oscillations in z direction) "disconnection" of the longitudinal electric field, which moderates electrons. Electron current injected into a trap is I_c=300 A, time of moderating electric field disconnection is τ_capt. ⁼5 ns, so that the total number of electrons captured into a trap makes N_e= 10¹³ electrons, the retained electronic density is equal to n_e=2*10¹⁰ electrons/cm³, the volume occupied with electrons is V_e=500 cm³. Time of electrons retention in the trap makes τ_ret=10 sec, which makes it possible to produce the total number of multiple-charge ions at 10% probability of ionisation equal to around N_U+90-+82=2*10 ions. The number of ions with charge of U₊₉₀ will be less by another factor: N_U+90=2*10⁹ ions at the frequency of source actuation F=0.1 Hz. Ions are discharged from the ionisation area for the time τ_rel=1 mcs due to their exposure to a longitudinal electric field, accelerated to the speed of β_z=0.01 in the electrostatic field U_el.st.=130 kV, transformed into a beam parallel to the axis z, with a pair of magnetic lenses having H_φ field: H_φ≈800 Gs, and separated by charges with a magnetic field of a rotary magnet having a vertical component H_vert, equal to H_vert=4 kGs. Afterwards the ion beam may be accelerated to the required energy in a linear or a cyclic accelerator.

EFFECT: generation of an ion beam of the required time duration.

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