Abstract: A photoionization sensor assembly includes a housing defining a chamber with a first end and an opposing second end and being permeable to the analyte gas and non-analyte gases. A radiation source is structured to emit photons into the chamber. A first, second and third electrode are positioned in the chamber. The photons ionize the analyte gas, are insufficient to ionize the non-analyte gases, and causing ejection of photoelectrons from the third electrode. A controller is structured to receive a measurement of a total pressure and electrically bias the electrodes to collect the photoelectrons on the first and second electrodes in a ratio dependent on the total pressure. The controller is structured to determine the ratio of photoelectrons that are collected on the first and second electrodes at the total pressure and determine an amount of electrical current due to ionization by correcting the measured current using the determined ratio.

Abstract: An ion source assembly for use in a mass spectrometer comprises a first anode defining a first ionization volume and a first electron source positioned proximate the first anode and configured to generate electrons that pass through the first anode and into the first ionization volume. The ions source assembly further includes a second anode defining a second ionization volume and a second electron source positioned proximate to the second anode and configured to generate to generate electrons that pass through the second anode and into the second ionization volume. At least one optical element is positioned proximate the first ionization volume and defines an aperture. The first and second anodes and the first and second ionization volumes are positioned along an ion optical axis of the mass spectrometer, and the first anode is positioned between the second anode and the aperture.

Abstract: An ion source assembly for use in a mass spectrometer comprises a first anode defining a first ionization volume and a first electron source positioned proximate the first anode and configured to generate electrons that pass through the first anode and into the first ionization volume. The ions source assembly further includes a second anode defining a second ionization volume and a second electron source positioned proximate to the second anode and configured to generate to generate electrons that pass through the second anode and into the second ionization volume. At least one optical element is positioned proximate the first ionization volume and defines an aperture. The first and second anodes and the first and second ionization volumes are positioned along an ion optical axis of the mass spectrometer, and the first anode is positioned between the second anode and the aperture.

Abstract: Systems for a managing a chemical process and photoionization detectors for analyzing a process gas are presented. In one aspect, the system includes a process gas source in fluid communication with the process chamber and a photoionization detector. The photoionization detector is configured to analyze the process gas. The photoionization detector includes a heat resistant coupling for connection to the system, a gas sample chamber with the radiation window soldered or brazed to a wall of the gas sample chamber, and a radiation source configured to emit radiation through the radiation window and into the gas sample chamber to analyze the process gas. In another aspect, the photoionization detector includes a removable coupling, a gas sample chamber, and a radiation source. The removable coupling is for connection to the process gas handling system and includes a metal gasket and metal flanges.

Abstract: Systems for a managing a chemical process and photoionization detectors for analyzing a process gas are presented. In one aspect, the system includes a process gas source in fluid communication with the process chamber and a photoionization detector. The photoionization detector is configured to analyze the process gas. The photoionization detector includes a heat resistant coupling for connection to the system, a gas sample chamber with the radiation window soldered or brazed to a wall of the gas sample chamber, and a radiation source configured to emit radiation through the radiation window and into the gas sample chamber to analyze the process gas. In another aspect, the photoionization detector includes a removable coupling, a gas sample chamber, and a radiation source. The removable coupling is for connection to the process gas handling system and includes a metal gasket and metal flanges.