Precision magnetic field monitoring in high radiation environments
AssigneeBoard of Trustees of Michigan State University
InventorsGeorg Bollen, Ryan Ringle
Life of this patent
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Abstract
A high-precision magnetometer based on a miniature Penning trap is used to measure high magnetic field strengths with very high accuracy. Due to the high precision of the developed miniature charged particle trap, magnetic field strengths can be measured with an accuracy of 1 part per million or greater, including up to and above 1 part per billion. The charged particle trap has been configured to operate with such precision in environments of high radiation, e.g., 1 MGy or above.
Claims13
A device for measuring magnetic fields in a high radiation field environment, the device comprising:
- a charged particle trapping structure comprising two opposing end cap electrodes each on opposite ends of a central ring electrode structure, the opposing electrodes and the ring electrode structure collectively defining an inner chamber, with the inner chamber adapted (i) for generation of charged particles within the inner chamber through ionization of neutral atoms or molecules and adapted for trapping generated charged particles or (ii) for the capture and trapping of externally generated charged particles, in the presence of a magnetic field and a static electric potential created from voltages supplied to the charged particle trapping structure;
- a radio frequency generator coupled to the charged particle trapping structure to generate an electric field inside the inner chamber to excite or maintain cyclotron motion of the charged particles within the inner chamber, wherein the charged particle trapping structure is adapted to detect the cyclotron frequency of the charged particles within the inner chamber over an operating environment range of an accumulated radiation dose of 1 MGy or above;
- and
- an electronic detector adapted to determine a value of the detected cyclotron frequency and to determine a magnetic field strength of the magnetic from the cyclotron frequency.
A method for measuring the strength of a magnetic field, the method comprising:
- generating target charged particles within a Penning trap or injecting the target charged particles into the Penning trap;
- maintaining the target charged particles within the Penning trap, such that for a given trap radius and trap length, applying a static magnetic field and a quadrupole electric field within the Penning trap maintains the target charged particles within the Penning trap for at least a measurement cycle;
- measuring the cyclotron frequency using an image charge resonance detection technique measuring radial motion of the target charged particles;
- and
- determining a field strength of the magnetic field from the cyclotron frequency,
- wherein the Penning trap is sized for measuring the field strength with an accuracy of 10 parts per million or greater, over an operating environment radiation range of 1 MGy or above.
Dependencies are inferred from the claim text.