Gabrielse Research Group

Board of Trustees Professor Gerald Gabrielse, one of the world's leading practitioners of fundamental, low energy physics and an active member of the National Academy of Sciences, is relocating from Harvard to Northwestern to be the founding director of the Center for Fundamental Physics at Low Energy (CFP for short). An award-winning researcher and teacher, Gabrielse has chaired both the Harvard Physics Department and the Division of Atomic, Molecular and Optical Physics (DAMOP) of the American Physical Society, and he leads the international ATRAP Collaboration at CERN.

The Gabrielse research group tested the most precise prediction of the Standard Model of Particle Physics using the most precisely measured property of an elementary particle, made the most precise determination of the fine structure constant, tested the Standard Model's most fundamental symmetry to an exquisite precision, made one of the most stringent tests of Supersymmetry and other proposed improvements to the Standard Model, and started low energy antiproton and antihydrogen physics.

The design and construction of new laboratories and offices for the research group and the CFP are now underway. The new facilities should be ready for occupation by the end of the summer of 2017. Until the labs and offices are completed, the Gabrielse group webpage and a list of publications are being maintained at Harvard.

Recent Advances

Current Research Projects (Department Overview)


Lepton Magnetic Moments - one apparatus, many results (below) Supported by NSF AMO
Most accurate measurements of g/2 and a

ATRAP Antihydrogen Studies (summary from Physics Today) Supported by NSF and AFOSR
Penning-Ioffe trap for antihydrogen

Proton and Antiproton Magnetic Moments Supported by NSF and AFOSR
Our new measurement is 680 times more precise than all previous measurements

Investigation of a One-Electron Qubit
Planar Penning trap
  • Goal 1: To identify planar the first trap designs within which an electron qubit could be realized (Recent PRA)
  • Goal 2: To observe one electron suspended within a planar trap chip
  • Goal 3: To demonstrate a one-electron qubit for the first time
  • Goal 4: To couple one-electron qubits
  • Goal 5: To investigate a coupled array of one-electron qubits

    • PRA: consideration of two entangled electrons

ACME Search for the Electric Dipole Moment of an Electron
  • Use ThO molecule
  • Goal is a significantly improved electron EDM measurement or limit on a 5 year time scale

    • PRA: overview and initial progress

Sample of Completed Projects (Overview)


Why Does Sideband Mass Spectroscopy Work? Supported by NSF, AFOSR, and the Humboldt Foundation
What "deeper magic" makes the sideband frequency, ?+ + ?-, be a good approximation to the cyclotron frequency?

Comparing Q/M of the Antiproton and Proton to 9 Parts in 1011 Was supported by NSF AMO and AFOSR
Improving antiproton q/m by factor of almost a million
  • Most stringent test of CPT invariance with a baryon system
  • Nearly a million times more precise than previous CPT tests with baryons
  • Series of three measurements with increasing accuracy

Methods to Slow, Trap, Electron-Cool, and Accumulate Cold Antiprotons Was supported by NSF AMO and AFOSR
First antiproton trap
  • Developed by the Gabrielse group and TRAP collaborators
  • Used to get cold antiprotons for Q/M measurements
  • Used by and makes possible all cold antihydrogen experiments

Brown-Gabrielse Invariance Theorem Makes possible many of the most precise measurements in particle, atomic, and nuclear physics
  • Makes possible the most accurate measurements of magnetic moments
  • Makes possible the most accurate ion mass spectroscopy
  • Makes possible the most accurate nuclear mass spectrometry

Inventing Designs for Penning Traps Was supported by NSF AMO and AFOSR
Cylindrical Penning trap

Superconducting Solenoid that Shields Magnetic Field Fluctuations Was supported by NSF AMO, AFOSR, and NIST
  • Cancels by a factor of 250 or more any change in the external magnet field
  • A flux change in the solenoid produces a current, that produces a field, that cancels the field change at the center of the system
  • No active electronics
  • Made it possible to do antiproton Q/M measurements not far from cycling LEAR and PS magnets
  • Allows MRI imaging machines to be located nearer to elevators, etc.
  • Used for stable ICR mass spectrometry (e.g. to analyze pharmaceuticals)

Theory of One Particle in a Penning Trap Was supported by DOE and NSF
  • The often-cited basic review of the properties of a charged particle in a Penning trap

    • (click on cover image to download)

Immediate Opportunities

For new graduate students
Prospective graduate students interested in joining the Gabrielse group should apply for admission to the Northwestern Department of Physics and Astronomy before Dec. 31, 2018. Applications should clearly indicate interest in joining the Gabrielse group. Applicants should email their interest to Prof. Gabrielse and his administrative assistant.

For CFP fellows
CFP fellows will make the CFP an exciting, productive and visible center of excellence. Applicants for postdoc fellowship positions who are interested in working in the Gabrielse research group should email and his administrative assistant. Positions are available immediately. (Starting in 2018 an annual competition for CFP fellowships is anticipated.) Professor Gabrielse has collaborated with and supervised the PhD studies of nearly 50 Harvard students, and has also collaborated with and employed many Harvard postdocs. Group alums now have positions in universities, government labs, teaching colleges and in industry.

© 2015 - Last Updated: 08/31/2018 - Disclaimer