Scanning target

Abstract

The invention provides a scanning target. The scanning target is a scanning target for an accelerator neutron source. After an accelerator finishes acceleration of deuterium or deuterium-tritium mixed ion beams, ion beams are rapidly and uniformly spread into linear strip-shaped beam spots through a scanning magnetic field; spreading lengths surpass dozens of times the diameters of the beam spots; and then, the linear strip-shaped beam spots are bombarded onto a movable target in order to generate equivalent emission neutron beams having point source features in a direction parallel to a neutron target. The beam spots have high displacement speeds after scanning, and dwell time on each point is short, thereby causing low transient temperature rise. Meanwhile, a bombardment area on a target surface is uniformly widened by dozens of times; the average beam density is lowered by dozens of times; the average temperature rise is lowered greatly; and the target service life is prolonged. The scanning target is suitable for being applied to the neutron source needing directivity and a point source feature.

Description

technical field [0001] The invention belongs to the field of nuclear technology and application, and in particular relates to a scanning target. Background technique [0002] The neutron source of the accelerator uses the deuterium ions or deuterium-tritium mixed ions generated by the ion source. After being accelerated by the accelerating electric field, a certain amount of energy is obtained, and a D / D or D / T fusion reaction occurs on the target, and the neutron is released in the 4π direction. son. The neutron source of the accelerator has a high yield, no neutrons are generated after the power is turned off, it is easy to use, good in controllability and high in safety. [0003] When the high-energy ion beam of the accelerator neutron source bombards the target, high energy deposition is produced. Even under the condition of water cooling, the power density that the target can withstand must be controlled within a reasonable range to ensure the normal use of the target....

AI Technical Summary

Problems solved by technology

[0005] There are currently three ways to improve the ability of the target to withstand the deposition power: one is to use a swinging target to make the target surface mechanically swing. The advantage of this method is that the ion beam no longer just bombards the target surface without increasing the beam spot size. A point, but a surface, the average power is greatly reduced, the ion beam current can be increased, and the characteristics of the point source remain unchanged; the disadvantage is that the speed of the mechanical swing is not fast enough, the length of the expansion is limited, the volume is large, and at the same time it is rotating There is a pause at the edge of the target, and the transient temperature rise is relatively high. The deposition power density of a purely swinging target can be increased several times, and the increase is limited.

The second is "Rotating Target Intensive Neutron Source and Its Application" (Journal "Modern Physics Knowledge", No. 05, 1996) discloses a method of increasing the target area by rotating the target. The advantage of this method is that it can be used without Under the condition of increasing the beam spot size, through the high-speed rotation of the target surface, the instantaneous temperature rise and the average temperature rise are greatly reduced, thereby greatly improving the ability of the target to withstand the deposition power, thereby increasing the neutron yield and flux. The disadvantage is that the structure is complex, the volume is huge, and the rotation speed is extremely fast (1000-5000 rpm), it is very difficult to further increase the rotation speed, the reliability is poor, and the cost is high; the third is CN201010238639. A small neutron source with a window gas target. This method has the advantages of no fixed target, high output, and long target life. The disadvantage of this method is that it is extremely technically difficult, the volume of the vacuum system is large, the energy consumption is high, the cost is high, and the beam The spot scatters in the target and the point source characteristics deteriorate

[0006] At present, there is no neutron target that is economical, simple in structure, directional and point source

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