Soft X-ray production in spark discharges in hydrogen, nitrogen, air, argon and xenon gases

We describe a generator of soft X-rays of energy between 2 and 10 keV by sparking in hydrogen, air, nitrogen, argon and xenon gases at low pressure with a sparking voltage as low as ∼0.8 kV. The X-ray events appear to come in clusters, with an average mean multiplicity of 3 per single event into the solid angle of our detector; the extrapolated production into a 4π-solid angle is more than ∼1500 pulses per event, assuming the isotropic distribution. The device operates with the peak spark currents 0.2–0.5 kA and the total spark charge more than 4×1014 electrons/spark. The spark stored energy 0.024–0.17 J/pulse is more than four orders of magnitude smaller compared to experiments reporting similar X-ray production. The X-ray generator can be used as a simple monitor of the gaseous detectors, or a device to study various gaseous phenomena occurring in large sparks.