Observation of Extreme Ultraviolet Hydrogen Emission from Incandescently Heated Hydrogen Gas with Strontium that Produced an Optically Measured Power Balance that was 4000 Times the Control

We report the observation of intense extreme ultraviolet (EUV) emission from incandescently heated atomic hydrogen and atomized strontium. It has been reported that intense EUV emission was observed at low temperatures (e.g. ≈ 10 3 K) from atomic hydrogen and certain atomized elements or certain gaseous ions which ionize at integer multiples of the potential energy of atomic hydrogen, 27.2 eV [1-5]. Strontium ionizes at integer multiples of the potential energy of atomic hydrogen. Typically the emission of extreme ultraviolet light from hydrogen gas is achieved via a discharge at high voltage, a high power inductively coupled plasma, or a plasma created and heated to extreme temperatures by RF coupling (e.g. > 10 6 K) with confinement provided by a toroidal magnetic field. The observed plasma formed at low temperatures (e.g. ≈ 10 3 K) from atomic hydrogen generated at a tungsten filament that heated a titanium dissociator and atomic strontium which was vaporized from the metal by heating. No emission was observed when sodium, magnesium, or barium replaced strontium or when argon replaced hydrogen with strontium. The power balance of a gas cell having atomized hydrogen and strontium was measured by integrating the total light output corrected for spectrometer system response and energy over the visible range. A control cell was identical except that sodium replaced strontium. In this case, 4000 times the power of the strontium cell was required in order to achieve that same optically measured light output power. A plasma formed at a cell voltage of about 250 volts in the cell with hydrogen alone and in the cell with hydrogen and sodium; whereas, a plasma formed in the strontium cell at the extremely low voltage of about 2 volts.