Abstract: An ion source is formed by a chamber 2. A capillary tube 6 forms an inlet to the chamber. A heater 7 is associated with the capillary tube to heat air drawn into the chamber. An electrode 4 is provided in the chamber and maintained at a voltage in the range 100 to 500 volts. In use the source is connected to an analyzer such as a mass spectrometer 10. The capillary tube is open to the atmosphere. Pressure in the chamber is reduced, and pressure in the analyzer is further reduced. An electrical potential is applied to the electrode to create a discharge within the chamber. Ionization of air molecules within the chamber leads to ionization of any sample molecules present in the chamber. Ions are swept into the analyzer for analysis.

Abstract: An ion source is formed by a chamber 2. A capillary tube 6 forms an inlet to the chamber. A heater 7 is associated with the capillary tube to heat air drawn into the chamber. An electrode 4 is provided in the chamber and maintained at a voltage in the range 100 to 500 volts. In use the source is connected to an analyser such as a mass spectrometer 10. The capillary tube is open to the atmosphere. Pressure in the chamber is reduced, and pressure in the analyser is further reduced. An electrical potential is applied to the electrode to create a discharge within the chamber. Ionisation of air molecules within the chamber leads to ionisation of any sample molecules present in the chamber. Ions are swept into the analyser for analysis.

Abstract: A charged particle buncher with a series of spaced apart electrodes 1 arranged to generate a shaped electric field, the series comprising a first electrode 1a, a last electrode 1b and one or more intermediate electrodes, wherein the shaped electric field is generated substantially without free charges being transferred onto or away from the intermediate electrode or electrodes. The first and last electrodes may be connected to means for transferring charged on to or off the electrode. The first, intermediate and last electrodes may be connected in serried with capacitors.

Abstract: A charged particle buncher with a series of spaced apart electrodes 1 arranged to generate a shaped electric field, the series comprising a first electrode 1a, a last electrode 1b and one or more intermediate electrodes, wherein the shaped electric field is generated substantially without free charges being transferred onto or away from the intermediate electrode or electrodes. The first and last electrodes may be connected to means for transferring charged on to or off the electrode. The first, intermediate and last electrodes may be connected in serried with capacitors.