SU360900A1 - Accelerator path direct action - Google Patents

Description

(54) DIRECT ACTION OF ACCELERATOR

This invention relates to devices for accelerating charged particles in an electric field.

Designs of direct paths of accelerators are known, in which the acceleration of a beam of charged particles is effected by an electrostatic field. Based elements of the acceleration tract; are the accelerator source; Ne, the accelerator tube itself, is a set of metal eletrod separated by dielectric inserts and equipped with one or several flanges for connecting a vacuum on iCocoB, a tube evacuation system and

a high voltage divider connected to an accelerating voltage source and consisting of a chain of resistors connected to the electrodes. Vacuum pumping of the tube is carried out by pumps placed on one or both of the tubes.

However, as one goes to high values of accelerating voltage (above several jHaB) eff |.}; The activity of the known constructions is sharply reduced. Eg9 connected

Since, with an increase in the accelerating voltage, the length of the accelerating tube inevitably increases on average in proportion to the accelerating voltage, the conductivity of the tube turns out to be relatively small. As a result, in the operating mode along the length of the tube, due to the desorption flows, a significant pressure differential occurs, reaching mm Hg. Art. To reduce the differential, it is necessary to increase the diameter of the tube, that is, the dimensions of the entire accelerator and its cost.

In the proposed {{th} construction of the accelerator path inside the tube, one or several pumping elements are placed along its length, and the power supply to these elements comes from the High Voltage Divider.

Claims (2)

This makes it possible to improve the pumping system and the operational characteristics of the path and eliminate the effect of current variations consumed by the discharge on the stability of the high-voltage divider. ryant. The path contains an acceleration tube 1, a negative electrode 2 of a source of accelerating voltage, a positive electrode 3, resistors 4 of a high-voltage divider, electrodes 5 of an accelerating tube, a yatode 6 of the magnetic discharge pump element, an anode 7 of the magnetic discharge pump element, permanent magnets 8 system evacuation 9. Inside the accelerating tube, to the extreme parts of which negative and positive electrodes of the accelerating voltage source are connected and in parallel with which a high-voltage resistor circuit is connected The divider connected to the electrodes of the accelerator tube is installed with gaps of 3-5 mm cathodes 6, made of actively gas-absorbing metals, such as titanium and zirconium, and a metal anode 7 of cellular form. Permanent magnets 8 are placed in the immediate vicinity of an anodic-cathode block formed in this manner with a free central part, creating an axial magnetic beam, so that the discharge pump is placed inside the accelerator tube. The cathodes 6 and the anode 7 are electrically connected to the corresponding terminals of one of the resistors of the high-voltage divider. When applied to the tube, the accelerating voltage is due to high voltage deli. The body along the length of the tube creates a close to uniformly distributed electrostatic field, and a potential difference of about 10 kV arises between the cathodes 6 and the anode 7 of the magnetic discharge element. In this case, a discharge occurs in the interelectrode space of the anode-cathode block, leading to the sputtering of the cathode material and the active binding of residual gases inside the accelerating tube, as a result of which its operational characteristics are significantly improved. With external and internal diameters of the anode-cathode block of 400 and 80 mm, respectively, the magnetic discharge element with a height of 30 mm (without taking into account permanent magnets placed outside the tube) is able to provide pumping speed in the order of 50 l / C-.c {through the air), which allows the gas flow to be desorbed from a section of a tube with a length of several meters and drastically reduce the pressure of the residual gases of the BiijTpn tube. the element arising during its operation, the discharge current does not exceed 15–20 μA, which is substantially less than the current of the high-voltage divider. Therefore, the discharge gap in the operating mode has a relatively Weak effect on the distribution of the potential across the resistor to the terminals of which it is connected. The presence of one or several magneto-discharge pumping elements practically does not affect the electrical stability and operation stability of the entire divider, since the number of series-connected resistors of a high-voltage divider for a tandem accelerator by 30 MeV exceeds 350, and even significant changes in the conductivity of one or several of them due to the change in any current, post | The release of the magnetic discharge pumping elements has a very weak effect on the conductivity of the entire divider. If necessary, the anomically-cathode block of the magnetic discharge pumping element can be connected to the resistor of the high-voltage divider through a chain of active Hbiix non-linear resistors selected so that in the working pressure range of the accelerator the shunt conductivity divider remains constant. In this case, the magnetic discharge of the pumping element does not affect the parameters of the divider and the stability of the high voltage source at all. Claim 1. A direct-action accelerator path containing an accelerating voltage source, an accelerator tube, an evacuation system and a high-voltage divider, characterized in that, in order to improve the pumping system and the performance characteristics of the tube, in the internal cavity of the latter its length is discharge discharge elements, the electrodes of which are electrically connected to one or several sections (resistors) of the high-voltage divider. 2. The path according to claim 1, characterized in that, in order to eliminate the effect of changes in the current consumed by the discharge pumping elements, on the stability of the high-voltage divider, the pumping elements are connected to the latter through a chain of active non-linear resistors, chosen in such a way so that in the working pressure range inside the tube the conductivity of the shunt divider remains unchanged.