ГЭТ 72-2001 (НИО 210)
Standard name:
- ГЭТ 72-2001 State primary standard of units of electron flux, electron flux density and electron fluence (transfer), energy flux, energy flux density and fluence (transfer) of electron and bremsstrahlung energy.
Type of measurement:
- Measurements of ionizing radiation characteristics and nuclear constants
Structural division: name НИО\НИЛ:
- Research Department for Measurements of Ionizing Radiation
Guardian Scientist:
- Tsvetkov Igor Ivanovich
Year of creation:
- 1975
Year of re-confirmation:
- 2001
Operating principle:
In the state primary standard GET 72-2001, units are reproduced using several absolute methods. The unit reproduction procedure is based on the theory of the interaction of ionizing radiation with matter (charge, calorimetric, and ionization methods) and the laws of electromagnetism (electrophysical method) for a flow of accelerated charged particles. Measurement equations for reproducing units use fundamental physical constants, including radiometric and dosimetric constants. Proportionality coefficients in measurement equations reflect the specific design features of each type of primary measuring transducer.
Composition of the standard:
The state standard consists of a set of primary measuring transducers, precision instruments for measuring electrical quantities: current, charge, voltage and resistance; auxiliary devices - the KS-AT 130 calibration stand, the UEL 5/20 linear electron accelerator, the ATOMTEKH electron monochromator, a set of BIS-10-BIS-50 radionuclide sources and special engineering structures.
Комплект эталонных первичных измерительных преобразователей включает в себя:
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Primary measuring charge converters – Faraday cups (ЦФ): ЦФ-3, ЦФ-РЭП, ЦФ-4, ЦФ-Э; для reproduction of a unit of electron flow with a maximum electron radiation energy from 0.01 to 50 MeV (Figure 1)
a) a digital filter set for narrow and wide electron beams; b) a digital filter set for unfolded electron beams./Рисунок-1а.png)
Figure-1a /Рисунок-1б.png)
Figure-1b -
Primary measuring calorimetric converters – energy flow calorimeters:КПЭ, ДОК-1, ДОК-2, КЦФ-1, КЦФ-РЭП, КЭС-1С;to reproduce units of energy flux, energy flux density and fluence (transfer) of energy of electron and bremsstrahlung radiation with a maximum energy of electron radiation from 0.1 to 50 MeV (Figure 2);
/Рисунок-2a.png)
Figure-2a /Рисунок-2б.png)
Figure-2b /Рисунок-2в.png)
Figure-2c /Рисунок-2г.png)
Figure-2d
Figure-2e Рисунок 2 - Первичные измерительные калориметрические преобразователи - калориметры: а) - КПЭ, b) – ДОК-2, c) – КЦФ-1, d) – КЦФ-РЭП
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Primary measuring ionization transducers – ionization chambers ИК: ИКВ-6.1, ИКВ-6, Р2, TN30010, ; to reproduce units of energy flux, energy flux density and fluence (transfer) of energy of electron and bremsstrahlung radiation with a maximum energy of electron radiation from 0.01 to 50 MeV (Figure 3);
/Рисунок-3a.png)
Figure-3a /Рисунок-3б.png)
Figure-3b /Рисунок-3в.png)
Figure-3c /Рисунок-3г.png)
Figure-3d Figure 3 - Primary ionization measuring transducers - ionization chambers: a) – ИКВ-6, b) – ИКВ-6.1, Р-2, c) – ИКВ-4, d) –type TN30010, 34001
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Primary measuring diamond and semiconductor converters for transmitting units of electron flux density (charged particle flux density), energy flux density of electron and bremsstrahlung radiation with a maximum radiation energy from 0.1 to 50 MeV (Figure 4);
/Рисунок-4.png)
Figure-4 Figure 4 - Primary measuring diamond type УДМс-1к,САД-1и semiconductor converter Diode P 60012.
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Primary measuring magnetic-induction transducers MIP for reproducing a unit of electron flow (flow of charged particles) with a maximum energy of electron radiation from 5 to 50 MeV (Figure 5);
/Рисунок-5a.png)
Figure-5a /Рисунок-5б.png)
Figure-5a Figure 5 - Primary measuring magnetic induction transducers. а) - МИП -10; b) – МИП 1000; c) – МИП-В.
The linear electron accelerator UEL 5/20 (Figure 6) as part of the standard has the features of an experimental setup with the following characteristics:
- Source of electron and bremsstrahlung radiation;
- Two directions of radiation beam propagation: vertical at a base of up to 2 m and horizontal for electron and bremsstrahlung at a base of up to 7 m;
- In the horizontal direction the following radiation fields are realized:
- Narrow electron beam (beam diameter 5.0 mm),
- Wide electron beam (at a distance of 1.0 m from the output window 100x100 mm and at a distance of 7.0 m 400x400 mm),
- Wide beam of bremsstrahlung (at a distance of 1.0 m from the target 100x100 mm and at a distance of 7.0 m 400x400 mm);
- Discrete regulation of radiation energy in the range from 5 to 20 MeV (at least five to six values);
- Smooth regulation of the average current of the accelerated electron beam in the range from 0.1 to 2.0 μA;
-
Availability:
- Rotating magnet spectrometer;
- Calibration stand KS-AT130 with a base of up to 7 m;
- A radiation head with six positions, two of which have tungsten targets with a thickness of 2.0 and 6.0 mm, two generate electron fields, and the rest are for experimental work;
/Рисунок-6а.png)
Figure-6a /Рисунок-6б.png)
Figure-6b Figure 6 - Experimental hall of the standard: a) Linear electron accelerator УЭЛ 5/20; b) experimental hall of the standard with a calibration stand КС-АТ130
Electron monochromator МЭН-2Э- Electromagnetic spectrometer of electron radiation (radionuclide beta-radiation source in the design БИС-10) in the energy range from 20 to 3000 keV (Figure 7).
/Рисунок-7-1.png)
Figure-7-1 /Рисунок-7-2.png)
Figure-7-2 Figure 7 - General view of the MEN-2E monochromator.
Auxiliary devices that ensure the conditions for reproducing units include (Figures 6-8):
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Automated remote control systems for the movement of primary measuring transducers in radiation fields;
/Рисунок-8.png)
Figure-8 /Рисунок-8а.png)
Figure-8a /Рисунок-8б.png)
Figure-8b Figure 8 - Devices for remote movement of primary measuring transducers: a) single-coordinate moving devices; b) two-coordinate moving devices
- Automated measuring and computing complex equipped with software for collecting, processing and presenting measurement results (Figure 9)
/Рисунок-9-1.png)
Figure-9 /Рисунок-9-2.png)
Figure-9 Figure 9 - Measuring and computing complex of the state primary standard ГЭТ 72-2001.
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A set of phantom devices for reproducing and transmitting dosimetric units (Figure 10).
/Рисунок-10a.png)
Figure-10a /Рисунок-10б.png)
Figure-10b /Рисунок-10в-1.png)
Figure-10c-1 /Рисунок-10в-2.png)
Figure-10c-2 /Рисунок-10г.png)
Figure-10d /Рисунок-10д.png)
Figure-10e /Рисунок-10е.png)
Figure-10f Figure 8 - Phantom device complex for reproducing and transmitting dosimetric units:
a) air-water three-coordinate phantom;
b) water phantom;
c) single-coordinate solid (graphite, plexiglass) phantoms;
d) phantom caps for "electronic equilibrium";
e) volumetric solid-state (PMMA, aluminum, graphite) phantoms
f) phantom «Клин Al».
Main metrological characteristics
Metrological parameters and characteristics of the state primary standard in reproducing units of electron flux - ФN, c-1, electron flux density - φN,c-1∙cm-2, and electron fluence (transfer) - ΨN, cm-2, energy flux - Ф_E, W, energy flux density - φ_(E ), W∙cm-2 and energy fluence (transfer) - Ψ_E, J∙cm-2, electron and bremsstrahlung radiation with electron energy up to 50 MeV.
| Name of physical quantity | Range of values | S0 | q0 | u0А | u0В | u0С | U0 |
|---|---|---|---|---|---|---|---|
| Electron flux, s-1 | from 1010 to 1021 | no more than 5 x 10-3 | 1 x 10-2 | no more than 5 x 10-3 | 5 x 10-3 | 7.1 x 10-3 | 1.4 x 10-2 |
| electron flux density, cm-2 s-1 | from 108 to 1019 | 2 10-2 | 1.1 10-2 | 1.2 10-2 | 2.4 10-2 | ||
| electron transfer, cm-2 | from 109 to 1021 | no more than 5 x 10-3 | 2 x 10-2 | no more than 5 x 10-3 | 1.1 x 10-2 | 1.2 x 10-2 | 2.4 x 10-2 |
| Energy flux, W | from 10-4 to 103 | 1 x 10-2 | 5 x 10-3 | 7.1 x 10-3 | 1.4 x 10-2 | ||
| Energy flux density, W cm-2 | from 10-5 to 102 | no more than 5·10-3 | 2·10-2 | no more than 5·10-3 | 1.1·10-2 | 1.2·10-2 | 2.4·10-2 |
| energy transfer, J·cm-2 | from 10-3 to 103 | 2·10-2 | 1.1·10-2 | 1.2·10-2 | 2.4·10-2 |
where S0 are the standard deviations of the measurement results;
q0 are the unremoved components of the systematic error;
u0 are the expanded uncertainties of the measurement results with a coverage factor of k = 2;
u0A are the standard uncertainties assessed according to Type A;
u0B are the standard uncertainties assessed according to Type B.
Additionally, based on the results of measurements of energy flux density and bremsstrahlung energy transfer, the measuring instruments of the state primary standard GET 72-2001 are used to measure the dosimetric quantities listed in Table 2.
Metrological characteristics for measuring dosimetric quantities.
| Measuring Instruments | Physical Quantity | Range of the Measured Quantity | Expanded Uncertainty, U, at k = 2, % |
|---|---|---|---|
| Dosimeter | Energy flux density | from 1.0∙10-6 to 1.0∙103 W cm-2 | 2.4 |
| Energy transfer (fluence) | from 10-3 to 103 J cm-2 | 2.4 | |
| Absorbed energy in a standard material | from 1.0∙10-5 to 1.0∙103 J kg-1 | 2,4 | |
| Air Kerma | 1.0∙10-5 to 1.0∙103 Gy | 2.5 | |
| Air Kerma Rate | 1.0∙10-8 to 1.7∙102 Gy/s | 2.5 | |
| Ambient Dose Equivalent | 1.0∙10-2 to 1.0∙103 Sv | 3.0 | |
| Ambient dose equivalent rate | from 5.0∙10-5 to 3.0∙102 Sv/h | 3.0 |
Verification diagram:
- ГОСТ 8.576-01. ГЭТ 72-2001 is the head of the state verification scheme for measuring instruments for electron flux, electron flux density and fluence (transfer) of electrons, energy flux, energy flux density and fluence (transfer) of electron and bremsstrahlung energy.
Scope of application:
The composition of the state primary standard, its technical and metrological parameters and characteristics make it possible to provide metrological support in the measurement practice of the following areas:
- Integrated computerized measuring instruments for accelerator complexes,
- Measuring channels in accelerator radiation field diagnostic and monitoring systems (classified as high-precision working measuring instruments – HMI);
- Dosimetric and radiometric measuring instruments used for radiation field certification during commissioning and accelerator operation (classified as working standards – РЭ);
- Test and calibration rigs for pre-flight calibration of space monitoring equipment (working standards - РЭ);
- Test rigs for dosimetric and radiometric measuring instruments in high-energy ionizing radiation fields for radiation resistance;
- Calibration stands for individual dosimeters with an energy range of up to 20 MeV for crews of space and aircraft, personnel servicing accelerator complexes;
- Dosimeters with an energy range of up to 20 MeV for organizations monitoring the operating conditions of accelerator complexes, including the quality of stationary protection and local protective devices.
Results of applying the standard:
The fleet of reference measuring instruments is used to certify radiation fields:
- Experimental (pilot) samples of electron accelerators;
- Accelerator-flaw detectors;
- Accelerators for radiation technologies;
- Accelerator-sterilizers;
- Accelerators used as test equipment (TE), according to ГОСТ Р 8.568-2017, ГОСТ РВ 0008-002-2013
The total number of measuring instruments traceable to ГЭТ 72-2001:
By 2025, the fleet of electron accelerators used in science, industry, medicine, and specialized fields is estimated to number 450-500, excluding foreign deliveries. Each accelerator has at least one built-in primary measuring transducer and up to two external (portable) dosimetric and radiometric measuring instruments.
Ensuring the uniformity of measurements, participation in the CIPM MRA program:
13
Unique technical installations as part of the standard:
Linear electron accelerator УЭЛ 5/20
Electron monochromator МЭН-2Э
A set of technical installations, primary measuring transducers and computer software, including software for collecting, processing and presenting measurement results during the reproduction and transmission of units (software “Calormeter v.1.2”, “D3Field v1.”, “iPluse v 1.4.3”, “Pixe Profile”, “iFLUX v.1”.