Large area multiwire proportional counter

       In ionizing radiation measurement, alpha and beta radioactive source measurement is a very important part of the radioactive activity measurement system. The surface emissivity of the alpha and beta radioactive source can be used as a activity reference source or a test source to measure the scale and calibration of the instrument as well as the measurement of the radioactivity of the environmental samples as a standard of radioactivity measurement. The main measuring device of alpha and beta radioactive plane source is a large area of 2 pi multi wire proportional counter. The multifilament proportional counter is close to 100% detection efficiency for the measurement of alpha and beta radioactive plane sources. It is an absolute measurement method for 2 pi radioactive plane sources.

Technical characteristics：

1, in order to reduce the measurement background and improve the measurement accuracy, the anti coincidence technology is adopted.
2, integrated electronics circuit, instead of the traditional NIM plug-in, makes the system operation simpler and more reliable.
3. Special measuring software can set up various measuring conditions, and can show the plateau curve, and the results are clear at a glance.
4, the whole cabinet type design, the system integration is high.

Main technical indicators

(1) 1, active sample area: 1521cm;
(2) multi wire chamber volume: 39cm (long) x 39cm (wide) x 7cm (high);
(3) plateau characteristics: 241Am source: flat slope is superior to 1%/100V 90Sr-90Y source: Ping tilt is better than 2%/100V.
(4) background count rate: alpha source is not greater than 0.001cm-2*S-1; beta source is not greater than 0.05 cm-2*S-1
(5) repeatability: better than 1%
(6) surface emissivity: the relative deviation from the nominal value is within + 2%.
(7) the extended uncertainty is better than 1% (k=2)
(8) power supply: 220V 50Hz;
(9) the velocity of gas flow: 0 ~ 200sccm;