DECRIS-PM Ion Source


DECRIS-PM Ion Source

DECRIS-PM is a permanent magnet ECR ion source designed and manufactured for DC280 cyclotron of FLNR JINR. Accelerated ion beams of up to 10 pμA should be produced during the next several years to increase the efficiency of  DC280 cyclotron experiments on synthesis of the new heaviest elements.

The required intensities of some ECR source beams
Ion 8Ca8+ 58Fe10+ 136Xe23+ 238U40+
Beam intensity at the output of the ECR source, μA 150 125 150 1
Beam intensity at the physical target, part./s 5 x 1013 4 x 1013 2 x 1013 1 x 1011

DC-280 cyclotron injection system is equipped with two high voltage platforms. This makes it possible to efficiently accelerate ion beams from helium to uranium of 4-7 M/Q ratio.

DECRIS-PM ECR ion source is installed on the one of these HV-platform and is used for production of intermediate-mass ions (from He to Kr).

The main advantages of PM ECRIS sources are their low power consumption, low pressure in the water cooling system, ease of control, etc. Among their disadvantages the principal ones are fixed magnetic field distribution and comparatively low field strength. So the magnetic system configuration should be optimized properly already when being designed. Another disadvantage is strong mechanical interaction between separate parts of the system, which makes magnetic field correction after the system assembly almost impossible.

DECRIS-PM magnet system​

Magnetic structure of DECRIS-PM

1 ÷ 5 ÷ PM rings; 6, 7 – soft iron rings;

8 ÷ 11 – soft iron plates,

12 ÷ 14 – auxiliary elements,

15 – hexapole, 16 – coil.

DECRIS-PM parameters
  Working friequency 14GHz
  Injection magnetic field Binj ≥ 1.3 T
  Minimum magnetic field Bmin 0.4 T
  Extraction magnetic field Bextr 1.0÷1.1 T
  Radial magnetic field Br 1.05÷1.15 T
  Plasma chamber internal diameter 70 mm