TUTCRIS - Tampereen teknillinen yliopisto

TUTCRIS

Making radioluminescence detectable in wavelength regimes <300nm by modifying the gas concentrations around the radioactive source

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Yksityiskohdat

AlkuperäiskieliEnglanti
Tuotoksen mediaWritten report
Sivumäärä6
TilaSubmitted - 8 elokuuta 2016

Tiivistelmä

The presence of alpha particles in air generate excited Nitric Oxygen (NO*) that emits light at wavelengths from about 226 nm to about 270 nm, known as the NO gamma-band. The chemical reaction creating the NO* requires the presence of molecular Oxygen, O2. Too much of O2 however very quickly causes the intensity of emitted light to decrease (called quenching), making it impossible to exist.
Dondes et al. (1966) identify amounts of “close to 0.05%” of O2 in the air to balance NO* production and quenching in such a fashion that a maximum amount of light is detectable; the precise amount is unknown, though.

Modifying the gas concentrations around the alpha particle emitter with industrial nitrogen gas allows to create optimal conditions for gain a maximum of amount of light yield from NO*.
red. Under these conditions the light yield gained from a single line within the NO gamma-band can be as strong as the radioluminescence of the strongest N2 2+ system, the currently prevalent mechanism used to detect alpha particles from a distance by means of measuring radioluminescence.

The concept has been proven in a laboratory environment. A gust of Nitrogen gas has been used to clear the environment around an alpha emitter from oxygen. Diffusion of O2 back into the contaminated area eventually caused the formation of NO*, emitting light at 226.5nm. Further diffusion eventually causes the signal to decrease.