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David William Hertzog (born July 21, 1955) is an American particle physicist, known for his research in precision muon physics. [1] [2] [3]
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David William Hertzog (born July 21, 1955) is an American particle physicist, known for his research in precision muon physics. [1] [2] [3]
Hertzog graduated in 1977 with a bachelor's degree in physics from Wittenberg University in Springfield, Ohio. He received his doctorate in 1983 from the College of William & Mary. As a postdoc, from 1983 to 1986 he was a research associate at Carnegie Mellon University. At the University of Illinois Urbana-Champaign he was from 1986 to 1992 an assistant professor, from 1992 to 1997 an associate professor, and from 1997 to 2010 a full professor. In 2010 he became a professor at the University of Washington, where he is Arthur B. McDonald Distinguished Professor of Physics and director of the Center for Experimental Nuclear Physics and Astrophysics (CENPA). [4]
Hertzog has gained an international reputation for precision measurements of the muon. At Brookhaven National Laboratory in the early 2000s he played an important role in measurements of the muon magnetic anomaly. [5] [6] [7] [8] At the Paul Scherrer Institute, he was a co-leader of the science team for the MuLan experiment that measured the muon lifetime to 1-ppm and determined the Fermi constant to 0.5-ppm. [9] In 2021 he collaborated in the Fermilab Muon g-2 experiment that found a statistical discrepancy for the positive muon magnetic anomaly between the experimental value and the Standard Model prediction. [10]
Hertzog developed Pb/SciFi (lead / scintillating fiber) calorimeters [11] and other novel instrumentation including the suite of PbF2 calorimeters now used in high-precision measurements of the muon g-factor. [1]
He was elected in 2000 a Fellow der American Physical Society [12] and was awarded in 2004 a Guggenheim Fellowship. [13] In 2022 he received the Tom W. Bonner Prize in Nuclear Physics for "advancing the frontiers of understanding nature's fundamental symmetries via unprecedented precision studies of the muon, including its lifetime, its anomalous magnetic moment, and its measurement by the pseudoscalar coupling constant." [1]
In 1980 he married Nancy Beitman. [14] At the University of Washington she is a Professor of Learning Sciences and Human Development. [15]
A muon is an elementary particle similar to the electron, with an electric charge of −1 e and a spin of 1/2, but with a much greater mass. It is classified as a lepton. As with other leptons, the muon is not thought to be composed of any simpler particles; that is, it is a fundamental particle.
Main injector neutrino oscillation search (MINOS) was a particle physics experiment designed to study the phenomena of neutrino oscillations, first discovered by a Super-Kamiokande (Super-K) experiment in 1998. Neutrinos produced by the NuMI beamline at Fermilab near Chicago are observed at two detectors, one very close to where the beam is produced, and another much larger detector 735 km away in northern Minnesota.
In quantum electrodynamics, the anomalous magnetic moment of a particle is a contribution of effects of quantum mechanics, expressed by Feynman diagrams with loops, to the magnetic moment of that particle. The magnetic moment, also called magnetic dipole moment, is a measure of the strength of a magnetic source.
The DØ experiment was a worldwide collaboration of scientists conducting research on the fundamental nature of matter. DØ was one of two major experiments located at the Tevatron Collider at Fermilab in Batavia, Illinois. The Tevatron was the world's highest-energy accelerator from 1983 until 2009, when its energy was surpassed by the Large Hadron Collider. The DØ experiment stopped taking data in 2011, when the Tevatron shut down, but data analysis is still ongoing. The DØ detector is preserved in Fermilab's DØ Assembly Building as part of a historical exhibit for public tours.
The electron electric dipole momentde is an intrinsic property of an electron such that the potential energy is linearly related to the strength of the electric field:
CLEO was a general purpose particle detector at the Cornell Electron Storage Ring (CESR), and the name of the collaboration of physicists who operated the detector. The name CLEO is not an acronym; it is short for Cleopatra and was chosen to go with CESR. CESR was a particle accelerator designed to collide electrons and positrons at a center-of-mass energy of approximately 10 GeV. The energy of the accelerator was chosen before the first three bottom quark Upsilon resonances were discovered between 9.4 GeV and 10.4 GeV in 1977. The fourth Υ resonance, the Υ(4S), was slightly above the threshold for, and therefore ideal for the study of, B meson production.
T2K is a particle physics experiment studying the oscillations of the accelerator neutrinos. The experiment is conducted in Japan by the international cooperation of about 500 physicists and engineers with over 60 research institutions from several countries from Europe, Asia and North America and it is a recognized CERN experiment (RE13). T2K collected data within its first phase of operation from 2010 till 2021. The second phase of data taking is expected to start in 2023 and last until commencement of the successor of T2K – the Hyper-Kamiokande experiment in 2027.
A g-factor is a dimensionless quantity that characterizes the magnetic moment and angular momentum of an atom, a particle or the nucleus. It is essentially a proportionality constant that relates the different observed magnetic moments μ of a particle to their angular momentum quantum numbers and a unit of magnetic moment, usually the Bohr magneton or nuclear magneton. Its value is proportional to the gyromagnetic ratio.
Quantum electrodynamics (QED), a relativistic quantum field theory of electrodynamics, is among the most stringently tested theories in physics. The most precise and specific tests of QED consist of measurements of the electromagnetic fine-structure constant, α, in various physical systems. Checking the consistency of such measurements tests the theory.
Main Injector Experiment for ν-A, or MINERνA, is a neutrino scattering experiment which uses the NuMI beamline at Fermilab. MINERνA seeks to measure low energy neutrino interactions both in support of neutrino oscillation experiments and also to study the strong dynamics of the nucleon and nucleus that affect these interactions.
Gerald Gabrielse is an American physicist. He is the Board of Trustees Professor of Physics and director of the Center for Fundamental Physics at Northwestern University, and Emeritus George Vasmer Leverett Professor of Physics at Harvard University. He is primarily known for his experiments trapping and investigating antimatter, measuring the electron g-factor, and measuring the electron electric dipole moment. He has been described as "a leader in super-precise measurements of fundamental particles and the study of anti-matter."
Borexino is a deep underground particle physics experiment to study low energy (sub-MeV) solar neutrinos. The detector is the world's most radio-pure liquid scintillator calorimeter and is protected by 3,800 meters of water-equivalent depth. The scintillator is pseudocumene and PPO which is held in place by a thin nylon sphere. It is placed within a stainless steel sphere which holds the photomultiplier tubes (PMTs) used as signal detectors and is shielded by a water tank to protect it against external radiation. Outward pointing PMT's look for any outward facing light flashes to tag incoming cosmic muons that manage to penetrate the overburden of the mountain above. Neutrino energy can be determined through the number of photoelectrons measured in the PMT's. While the position can be determined by extrapolating the difference in arrival times of photons at PMT's throughout the chamber.
High-precision experiments could reveal small previously unseen differences between the behavior of matter and antimatter. This prospect is appealing to physicists because it may show that nature is not Lorentz symmetric.
Muon g − 2 is a particle physics experiment at Fermilab to measure the anomalous magnetic dipole moment of a muon to a precision of 0.14 ppm, which is a sensitive test of the Standard Model. It might also provide evidence of the existence of new particles.
In theoretical physics, the dual photon is a hypothetical elementary particle that is a dual of the photon under electric–magnetic duality which is predicted by some theoretical models, including M-theory.
Michel Davier is a French physicist.
Aida Xenia El-Khadra is a particle physicist who is a professor of high energy physics at the University of Illinois at Urbana–Champaign. She is the co-chair of the Muon g-2 Theory Initiative, which reported hints at new physics in the Standard Model in 2021. She is a fellow of the American Physical Society and the Alfred P. Sloan Foundation.
William Joseph Marciano is an American theoretical physicist, specializing in elementary particle physics.
Steven Michael Errede is an American experimental physicist, known for his leadership in the collaboration that experimentally confirmed the existence of the top quark.
The nucleon magnetic moments are the intrinsic magnetic dipole moments of the proton and neutron, symbols μp and μn. The nucleus of an atom comprises protons and neutrons, both nucleons that behave as small magnets. Their magnetic strengths are measured by their magnetic moments. The nucleons interact with normal matter through either the nuclear force or their magnetic moments, with the charged proton also interacting by the Coulomb force.
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