SU419164A1 - Device for transmitting information on the energy spectra of radioisotopes from several scintillation sensors to a multichannel amplitude pulse analyzer - Google Patents

Description

one

The invention relates to nuclear spectrometry and can be used to study the distribution of radioisotones in water.

Multi-channel pulse amplifiers are known, having several inputs and allowing the measurement of the energy spectra of radioisotols from several scintillation data simultaneously. At the same time, simultaneously with the measurement of the pulse amplitude from a certain zintilla zion sensor, the coordinate code of this sensor, generated by the analyzer encoder, is entered into the pulse analyzer arithmetic unit,

However, the presence of several analyzer inputs and an encoder for generating codes for the coordinates of the scintillation sensors significantly complicates the design of known analyzers and makes it impossible to use them to measure the energy spectra of radioisotopes from several sensors.

The purpose of the invention is to provide. The transmission of information over a single channel and simplify the device. To achieve this, each sensor is connected to a level discriminator and through a delay line to one of the inputs of a linear transmission device, the other two inputs of which are connected to the output of the level discriminator and the constant voltage level generator, and the output to the corresponding inputs of the cervical collecting circuit. The number of inputs of the circuit

equal to the number of. sensors used.

A block diagram of a device for transmitting information on the energy spectra of radioisotopes from several scintillation sensors (in this case, from four) to a multichannel amplitude analyzer is shown in the drawing.

Sensors 1–4, consisting of spectrometric NaJ scintillation crystals and photomultipliers (PMT), produce voltage pulses whose amplitudes are directly proportional to the energy of gamma rays of radioisotopes. The outputs of the sensors are connected to the corresponding delay lines 5-8, which delay the signals coming from the sensor outputs for the time required for the discriminators 9-12 of the level to be connected to the outputs of the sensors. Level 9-12 discriminators produce pulses only when

if the amplitudes of the pulses from the sensor outputs are as specified. The outputs of the discriminators are connected with linear transmissive devices (LPU) 13-16, the inputs of which are connected to the outputs of the delay lines 5-8. Designation of health facilities - skip without

distortion of pulses from the output of the delay lines in the presence of permissive pulses at the outputs of the level discriminators. Each LCP is also connected to a constant voltage level generator 17-20, intended to generate the voltage necessary to shift the spectrum of sensors to certain levels that are different for each sensor. The outputs of the LPU 13-16 are connected to the respective inputs of the linear collecting circuit 21, whereby information from several sensors is transmitted to the analyzer pulsed over a single wire.

The operation of the circuits of channels (in this case, four) is similar. The “radiation” signal causes a flash of light in the NaJ roll-out, which is amplified by the PMT of sensor 1. Thus, G1m: the voltage pulse at the output of the sensor is directly proportional to the y-quantum energy. This voltage pulse is applied to the delay line 5 and the discriminator 9 of the pulse level. The discriminator generates a pulse only if the pulse from the output of sensor 1 exceeds the lower discrimination level. And does not exceed the upper discrimination level. The discrimination levels of the discriminator 9 are chosen such that only those impulses that correspond to the photospic of the radioisotope under study are applied to the analyzer's input. Immersible from the output of the 9-level discriminator is fed to the LPU 13 and opens it. An input from an open LPU 13 receives a pulse from the output of sensor 1 with a delay 01 determined by the delay line. PAs 13–16 are supplied with voltage from 17-20 voltage level formers, therefore, at the outputs of the health facilities, impulses appear that differ from the impulses at their inputs only in that they are raised to the corresponding values. Output pulse

The LPU 13 is practically no different from the pulse at its input. Since the gains of the paths of the delayed-sensor-line sensor lines are the same for all sensors,

the difference between the amplitudes of the pulses at the outputs of the LPU 13-16, if the same pulses are applied to their inputs, is determined only by the levels of the transient voltages. Pulses from the outputs of the LPU 13-16 are fed to the corresponding inputs of the linear collecting circuit 21, from the output of which the pulses arrive at the input of the pulse analyzer. The photomultiplier gains of sensors 1-4 (or analyzer amplifier) are chosen such that

Photo centers of spectra of the studied radioisotope were located in the middle of the first zone of the analyzer. The sequential displacement of the spectra of sensors 2, 3, 4 relative to the spectrum of sensor 1 is determined by the levels of the voltage of the direct voltage of the drivers.

Claims (1)

Invention Formula A device for transmitting information on the energy spectra of radioisotopes from several scintillation sensors to a multichannel amplitude pulse analyzer, containing scintillation sensors and a linear collecting circuit, which is different from the fact that, from transmitting information through a single cable and simplifying the device, each sensor is connected to a level discriminator and through the delay line - with one of the INPUTS of the linear transmitting device, the other two inputs of which are connected to the output of the discriminator of the level and the driver The voltage level is constant, and the output is connected to the corresponding inputs of the linear collecting circuit, the number of which is equal to the number of sensors used. And analyzer , co5