Current saturation in free-air ionization chambers with chopped synchrotron radiation

被引：3

作者：

Nariyama, Nobuteru ^{[1
]}

机构：

[1] Japan Synchrotron Radiat Res Inst, Light Source & Opt Div, Sayo, Hyogo 6795198, Japan

来源：

JOURNAL OF SYNCHROTRON RADIATION | 2013年 / 20卷

关键词：

ionization chamber; X-ray chopper; ion recombination; pulsed X-rays; RECOMBINATION CORRECTION; ION RECOMBINATION; PARALLEL; COLLECTION; PHOTON;

D O I：

10.1107/S0909049513016154

中图分类号：

TH7 [仪器、仪表];

学科分类号：

0804 ; 080401 ; 081102 ;

摘要：

Saturation curves for free-air ionization chambers with electrode gap widths of 4.2, 8.4 and 18 mm were obtained for 10 and 15 keV undulator synchrotron radiation thinned with a 230 Hz rotating-disk chopper. Ion recombination in free-air ionization chambers was found to be inversely proportional to the applied electric field, and an expression that satisfactorily reproduced the ion-recombination rate is determined. A comparison of the expressions for continuous and pulsed X-rays revealed that chopped high-intensity X-rays require a higher voltage to attain saturation when the product of the pulse width and electric field exceeds a value that depends on the X-ray energy. This behaviour was observed explicitly for 10 keV X-rays in measurements with the ionization chamber placed before and after the chopper.

引用

页码：698 / 704

页数：7

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