Abstract. We demonstrate a new instrument for in situ detection of atmospheric iodine atoms and molecules based on atomic and molecular resonance and off-resonance ultraviolet fluorescence excited by lamp emission. The instrument combines the robustness, light weight, low power consumption and efficient excitation of radio-frequency discharge light sources with the high sensitivity of the photon counting technique. Calibration of I 2 fluorescence is achieved via quantitative detection of the molecule by Incoherent Broad Band Cavity-enhanced Absorption Spectroscopy. Atomic iodine fluorescence signal is calibrated by controlled broad band photolysis of known I 2 concentrations in the visible spectral range at atmospheric pressure. The instrument has been optimised in laboratory experiments to reach detection limits of 1.2 pptv for I atoms and 13 pptv for I 2 , for S/N = 1 and 10 min of integration time. The ROFLEX system has been deployed in a field campaign in northern Spain, representing the first concurrent observation of ambient mixing ratios of iodine atoms and molecules in the 1-350 pptv range.

A scheme is presented for pulsing of a cesium sputter negative ion source by periodically switching on and off the high voltage driving the sputtering process. We demonstrate how the pulsed ion beam can be used in combination with a pulsed laser (6 ns pulse length) that has a 10 Hz repetition rate to study the photodetachment process, where a negative ion is neutralized due to the absorption of a photon. In such experiments, where the ion beam is used only for a small fraction of the time, we show that the pulsed mode operation can increase the lifetime of a cathode by two orders of magnitude as compared with DC operation. We also investigate how the peak ion current compares with the ion current obtained when the source is run in a DC mode. We find that the peak current in the pulsed mode is strongly dependent on the ion species. In some cases, we observed a strong enhancement, whereas others showed only a moderate enhancement, or even a decrease, in the peak current. We conclude that the pulsed mode operation can be of great value when the negative ion to be investigated requires cathodes that have short lifetimes, expensive materials, or those with relatively small ion beam yields, in the latter case limited to elements with large enhancement factors.

We demonstrate a new instrument for in situ detection of atmospheric iodine atoms and molecules based on atomic and molecular resonance and off-resonance ultraviolet fluorescence excited by lamp emission. The instrument combines the robustness, light weight, low power consumption and efficient excitation of radio-frequency discharge light sources with the high sensitivity of the photon counting technique. Calibration of I₂ fluorescence is achieved via quantitative detection of the molecule by incoherent broad band cavity-enhanced absorption spectroscopy. Atomic iodine fluorescence signal is calibrated by controlled broad band photolysis of known I₂ concentrations in the visible spectral range at atmospheric pressure. The instrument has been optimised in laboratory experiments to reach detection limits of 1.2 pptv for I atoms and 20 pptv for I₂, for S/N=1 and 10 min of integration time. The ROFLEX system has been deployed in a field campaign in Northern Spain, representing the first concurrent observation of ambient mixing ratios of iodine atoms and molecules in the 1–350 pptv range

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The article provides a brief insight in the history of ion implantation, paying special attention to boron ion implantation in high purity Germanium crystal, exclusively valuable in the production of highly effective sensors of high-energy radiation to detect photons in the range of megaelectron-volt or higher up to hard X-ray range. There is a need for small user-friendly implanters in response to urgent demand to scale up production of short wave sensors, which are in exclusive demand for various nuclear safety systems worldwide. Particularly, research driven “high tech” small and medium enterprises in Latvia are among the three leading worldwide producers of such sensors and systems. These SME provide instrumentation to the International Atomic Energy Agency, to the government of Singapore, to the government of Japan to facilitate dealing with nuclear waste management caused by the Fukushima disaster, and to the European Space Agency. The challenge is to find technology that allows the use of solid state boron as ion sources instead of its chemical compounds, which create too many technological difficulties in the beam forming process and in most cases are poisonous. The review of existing solutions points towards a possible breakthrough where hollow cathode plasma combined with radiofrequency inductive coupled plasma can be used to produce boron ions from elemental boron in sufficient quantity to form a high energy ion beam close to 100 kV. Based on the review, promising solutions are offered, the first results of relevant analytic and pilot experiments are analysed and the future experimental roadmap is discussed.