Abstract: A system for measuring the density of a fluid in a vessel, the system including: at least one gamma-ray source positioned proximate to the vessel; at least one gamma-ray detector positioned proximate to the vessel, wherein the at least one gamma-ray detector is configured to detect gamma rays backscattered by the fluid from the at least one gamma-ray source; and a translator for converting the detected gamma-ray backscatter to a density value. A method to determine properties of a fluid in a vessel, the method including: positioning a gamma-ray source proximate to the vessel; positioning a gamma-ray detector proximate to the vessel; detecting gamma rays backscattered by the fluid from the gamma-ray source with the gamma-ray detector; determining a density of the fluid based upon an intensity of backscattered gamma rays received by the gamma-ray detector.

Abstract: System and methods for measuring the density, level, or interface position of a fluid or fluids in a vessel using gamma-ray backscatter are disclosed. The gamma-ray instruments disclosed may account for vessel wall buildup or deterioration. Methods disclosed herein include detecting gamma rays backscattered by a fluid from a gamma-ray source positioned proximate to a vessel with at least two gamma-ray detectors positioned proximate to the vessel and to each other; and determining a density, level, or interface value of the fluid based upon intensities of backscattered gamma rays received by the two or more gamma-ray detectors; wherein the vessel wall is subject to at least one of buildup and deterioration. The density, level, or interface may be a function of a ratio of the intensity of backscattered gamma rays received by two or more of the detectors.

Abstract: A system for measuring the density of a fluid in a vessel, the system including: at least one gamma-ray source positioned proximate to the vessel; at least one gamma-ray detector positioned proximate to the vessel, wherein the at least one gamma-ray detector is configured to detect gamma rays backscattered by the fluid from the at least one gamma-ray source; and a translator for converting the detected gamma-ray backscatter to a density value. A method to determine properties of a fluid in a vessel, the method including: positioning a gamma-ray source proximate to the vessel; positioning a gamma-ray detector proximate to the vessel; detecting gamma rays backscattered by the fluid from the gamma-ray source with the gamma-ray detector; determining a density of the fluid based upon an intensity of backscattered gamma rays received by the gamma-ray detector.

Abstract: A method for measuring high-energy radiation flux includes applying a positive voltage to electrodes in an ion chamber filled with a gas capable of forming charged ions by a high-energy radiation, measuring a positive ion current signal related to ion currents induced by the positive voltage, applying a negative voltage to the electrodes, measuring a negative signal related to ion currents induced by the negative voltage, and determining a magnitude of the high-energy radiation flux based on the ion current signal.