SU828902A1 - Ionization radiation detector - Google Patents

Abstract

1. IONIZING RADIATION DETECTOR containing two ionization cameras, which are switched on and formed by high-voltage and control electrode surfaces placed between the collecting electrode, characterized in that the purpose of extending the sensitivity adjustment range of the detector while maintaining the linearity of the operating characteristic that collects the electrode within the contour of the projections onto it of the high-voltage and control electrodes has holes, the characteristic linear dimensions of which are greater than the thickness of the collecting electric ekroda.2. Pop-up detector 1, which differs by the fact that, in order to ensure the highest possible sensitivity adjustment range, the apertures are evenly located on the electrode surface, their area is equal to the area of the collecting electrode, and the characteristic linear size of the apertures is 2 / 3 from the magnitude of the smaller electron gap. I (LSIS acquisition relates to the technique of measuring ionizing radiation and can be used in radiation and dosimetric instruments or in nuclear reactor control systems. Compensating Ionized chambers in which precise compensation adjustment is carried out by varying the degree of current saturation in the compensation part when adjusting the potential of the high-voltage electrode. However, decreasing the saturation level below 100% violates the linearity of the operating characteristics of the ionization chamber. containing two ionization chambers connected in opposite and formed by the surfaces of the high voltage and control electrodes and placed between them with Biranne electrode. In this chamber between high-voltage electrodes of different polarity a thin collecting electrode is placed, which is smaller than any of the high-voltage electrodes. This design allows the compensation of the compensation potential to be controlled by varying the potential of the compensating electrode, while at the same time ensuring the operation of both parts of the ionization chamber i in saturation mode and, therefore, maintaining the linearity of the operating characteristic. However, in such a design, it is sensitive, varies from one to another.

Description

at best, by a few percents, providing only compensation for the gamma background.

The aim of the invention is to expand the range of sensitivity adjustment of the detector while maintaining the linearity of the operating characteristic over a wide range of ionizing radiation intensity.

The goal is achieved by the fact that in a known detector ionizing ps of radiation, containing two ionized chambers, which are switched on and formed by the surfaces of high-voltage and control electrodes and a collecting electrode placed between them, collects the electrode within the contour of projections onto it of the high-voltage and control electrodes holes, the characteristic linear dimensions of which are greater than the thickness of the collecting electrode. In order to ensure the maximum possible sensitivity adjustment range, the apertures are evenly spaced over the electrode surface, i: the area is equal to the area of the collecting electrode, and the characteristic linear size of the apertures is 2/3 of the size of the smaller interelectrode gap,

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Figure 1 shows the total VCC collecting electrode and the scheme of the electrode system of the proposed detector; 2 is his adjustment characteristic, i.e. the dependence of the sensitivity of the detector on the voltage on the collecting electrode,

The detector contains a high-voltage 1 and control 2 electrodes, between which there is a collecting electrode 3. The overall dimensions of all electrodes are the same. The potentials V, V and V are applied to the electrodes 1,2,, 3, respectively, which provide counter-switching of the ionization chambers formed by pairs of electrodes 1-3 and 2-3. This condition is fulfilled, in particular, with, V2, O, UZ 0. Collecting electrode 3 is a plate with holes in the form of slits 4 located along the entire surface of the electrodes with schagom equal to double width of the slot.

Fig. 2 shows a typical curve of the dependence of the sensitivity of the detector on the magnitude of the voltage on the control electrode Vg at a constant voltage V. The thickness of the collecting electrode was 0.4 mm, the slot width was 1.1 mm, the distance from the collecting to high voltage 3.6 mm control electrodes and. 1.6 mm respectively. The sensitivity of the camera varies by 6 times while maintaining the linearity of the load characteristic over a wide range of ionizing radiation intensity.

The use of a detector with controlled sensitivity in instruments for monitoring ionizing radiation greatly simplifies the matching of the detector with amplifying and measuring equipment and extends the measurement range.

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Claims (1)

1. DETECTOR OF IONIZING RADIATIONS, containing two ionization ;. chambers connected counterclockwise and formed by the surfaces of the high voltage and control electrodes, a collecting electrode placed between them, characterized in that, for the purpose of expanding the range