# Todd Pedlar

Physics Department Head

## Biography

**Education:** Ph.D., Elementary Particle Physics, Northwestern University; B.A., Honors, Physics, Whitman College

Todd Pedlar has been a professor in the Physics Department since 2003. Some of his course topics include Classical Physics, Electricity and Magnetism, Quantum Mechanics, Nuclear and Particle Physics, and Thermal Physics. He also teaches in our common first-year course for all students: Paideia: Enduring Questions.

His research is in elementary particle physics, and he is a member of the Belle and Belle II collaborations: international teams that operate experiments at KEK, the National High Energy Research Organization in Tsukuba, Japan. More details on the research that Dr. Pedlar and his students do with Belle and Belle II can be found under “Research Interests” below.

Dr. Pedlar and his students are supported by grants from the National Science Foundation. He has been continuously funded by grants from the Elementary Particle Physics subdivision of the Mathematics and Physical Sciences division of the NSF. The latest grant, covering 2021-2024, is in the amount of $150,000.

This grant will continue to fund summer and academic-year research projects for him and for his students, travel to KEK for meetings and for the operation of the Belle II experiment, which began commissioning in early 2016 and formal operations in March, 2019. He and his students also regularly present the results of their work at both undergraduate conferences, the annual meetings of the American Physical Society, and international conferences such as the biennial International Conference on Heavy Quarks and Leptons.

Working on this research in Dr. Pedlar’s group has proven an excellent stepping stone for those seeking advanced degrees. Five of his last thirteen research students, graduating from Luther between 2012 and 2022, have gone on to Ph.D. programs in physics (at the University of Wisconsin-Madison, three at Indiana University, and Virginia Tech). Three other of the twelve are pursuing Ph.D. degrees in Materials Science at North Carolina State, in Electrical Engineering at Purdue University, and in Electrical Engineering at Cornell University. Of the remaining five research students graduating since 2012, one has received an MS in statistics from the University of Minnesota, one is pursuing an MD at the University of Iowa, and, finally, one is pursuing a J.D., a law degree with an emphasis in Patent Law, at the University of Texas-Austin.

Again, more info on Elementary Particle Physics Research at Luther College can be found on this page under “Research Interests.”

## Dr. Pedlar's Students Take Part in a Global Research Project

Dr. Pedlar has taught the following courses in the physics catalog:

**PHYS 112: Energy and the Physical World**

The unifying theme of energy molds the study of the physical concepts of motion, gravitation, electromagnetism, heat, radiation, and nuclear physics. Solar, wind, nuclear, tidal, hydroelectric, and thermal electric energy conversion processes are also included. This course is intended for the general student with no special background in mathematics or science.

**PHYS 152: General Physics II**

An investigation of the important principles of physics, including recent developments. Designed for the arts major as well as students majoring in one of the sciences. This course meets the basic requirements in physics for preprofessional students in health related fields, including medicine. Topics include mechanics, energy, fluids, heat, wave motion, electricity and magnetism, light and optics, and nuclear physics. Although this is a non-calculus course, the foundation of physics is mathematical modeling of the physical world. Thus, a basic working knowledge of algebra and trigonometry is assumed and will be further developed as the course proceeds. Graphical and statistical analysis is employed throughout the laboratory component.

**PHYS 181: Classical Physics I**

An introduction to the ideas of physics. Topics include Newtonian mechanics, energy, work, oscillations, and fluid dynamics. The laboratory work focuses on measurement and observation to enhance conceptual understanding of the material. The laboratory component is integral to the curriculum and is not offered as a separate course. Physics 181 is the first of a four-semester sequence of courses designed for physics and pre-engineering students. Physics 181 and 182 are also appropriate for students majoring in other physical sciences.

**PHYS 311: Advanced Laboratory I**

An introduction to linear circuits, including transistors and other solid state devices, techniques of electrical measurement, and application of electrical measurement techniques in experiments in modern physics.

**PHYS 359: Thermal Physics**

Concepts of entropy, temperature and thermodynamics. An emphasis on classical and quantum statistics with applications to a wide variety of physical systems.

**PHYS 364: Electricity and Magnetism**

A study of electric and magnetic fields leading up to Maxwell’s equations and their applications. The topics include the electrostatic and magnetostatic fields in vacuum and in matter, scalar potentials, vector potentials, electrodynamics and electromagnetic waves.

**PHYS 401: Particle and Nuclear Physics**

This course is intended to introduce students to the properties and interactions of nuclei and elementary particles. Attention will be paid both to the historical experimental development of these related fields as well as their theoretical aspects. Students will be introduced to nuclear properties including stability, structure and reactions, radioactivity and applications of fission and fusion. Among topics in particle physics that will be addressed are the quark model of hadrons, charged-lepton and neutrino physics, the strong and weak interactions, symmetries and conservations laws and experimental methods in particle physics.

**PHYS 411: Quantum Mechanics**

This course provides an introduction to the theory of nonrelativistic quantum mechanics. Both the conceptual and formal structure of the theory are discussed. A brief review of the experimental basis for quantization motivates the development of the Schrödinger wave equation. The principles of wave mechanics are then applied to various one dimensional problems, including the harmonic oscillator. The properties of angular momentum are developed and applied to central potentials in three dimensions. Matrix mechanics and spin angular momentum are also discussed, allowing for a complete treatment of the physics of hydrogen-like atoms.

- Ph.D., Elementary Particle Physics, Northwestern University, 1999
- Dissertation Title: “A Study of the Two-Photon Decays of Charmonium States Produced in Antiproton-Proton Annihilation”
- B.A.,
*Summa Cum Laude*and Department Honors, Physics, Whitman College, 1991 - Honors Thesis Title: “A Study of the Meissner Effect Using a Superconducting Pendulum”

### Elementary Particle Physics Research

Dr. Pedlar’s research interests are in elementary particle physics – specifically, the physics of heavy quarkonium systems known as bottomonium and charmonium. By studying the spectrum of states of heavy quarkonia – bound states of heavy quark and antiquark, the characteristics of the strong nuclear interaction, which holds together the quarks in protons and neutrons, may be precisely determined. Over the course of the past thirty years studying heavy quarkonia, Dr. Pedlar, his colleagues, and students have discovered several previously unobserved states of heavy quarkonia, observed particular decay modes for the first time, and as a result have been fortunate to be “in the drivers’ seat” as the strong interaction has increasingly become understood.

Pedlar and his students are supported by grants from the National Science Foundation, and have been continuously supported since 2006. He and his students are members of the Belle and Belle II collaborations – international teams that operate experiments at KEK, the National High Energy Research Organization in Tsukuba, Japan. The CERN Courier article, “Belle II super-B Factory Experiment Takes Shape at KEK,” explains the significance of the upcoming Belle II experiment, which began commissioning in early 2016, and started collecting data for physics analysis in 2018. The videos below also give a general introduction to this experiment.

Dr. Pedlar has been awarded six consecutive three-year grants from the Elementary Particle Physics subdivision of the Mathematics and Physical Sciences division of the NSF. The latest grant, covering 2021-24, is in the amount of $150,000. This grant will continue to fund summer and academic-year research projects for him and for his students, travel to KEK for meetings and for the operation of the Belle II experiment, and to support the operations of Pedlar’s Linux computing cluster at Luther. He and his students are active collaborators on physics analyses with others around the US and the world. In addition to working together on these studies, they also regularly present the results of their work at both undergraduate conferences, the annual meetings of the American Physical Society, and international conferences.

The activities of Belle II can be followed both Facebook and by following their Twitter account @belle2collab.

In June 2016, the end-caps of the Belle II Detector were closed, so that the collaboration could conduct some tests on parts of the new detector system that had been installed. A time-lapse video of the end-cap closing, which helps one appreciate the size and complexity of the Belle II detector system, appears here:

In April 2017, the Belle II detector was rolled into its nominal position on the electron-positron beamline so that it is in place to continue testing of both the hardware and software systems, and to be able detect the result of the first beam collisions of electron and positron beams during commissioning runs in early 2018:

Todd Pedlar’s CV (pdf)