# Edwin McMillan

> American physicist (1907-1991)

**Wikidata**: [Q19009](https://www.wikidata.org/wiki/Q19009)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Edwin_McMillan)  
**Source**: https://4ort.xyz/entity/edwin-mcmillan

## Summary
Edwin McMillan was an American physicist renowned for his pioneering contributions to nuclear physics and the development of the cyclotron. He is particularly noted for discovering the element neptunium and coining the term "nuclear fission," which significantly advanced atomic research.

## Biography
- Born: September 18, 1907, in Los Angeles, California, United States  
- Nationality: American (United States)  
- Education:  
  - Bachelor of Science from Caltech (1928)  
  - Doctorate from Princeton University (1932)  
- Known for: Discovery of neptunium, foundational work in nuclear fission, and advancements in particle acceleration  
- Employer(s):  
  - University of California, Berkeley  
  - California Institute of Technology  
- Field(s): Physics, Nuclear Physics, Particle Acceleration  

## Contributions
Edwin McMillan made several landmark contributions to science:
- **Discovery of Neptunium (1940)**: Working with Philip Abelson at the Berkeley Radiation Laboratory, McMillan identified the first transuranium element, neptunium, laying the groundwork for the actinide series.
- **Coining the Term "Nuclear Fission"**: He was among the first to use this term, helping to define and popularize the concept in nuclear physics.
- **Cyclotron Development**: McMillan contributed to the evolution of the cyclotron, a particle accelerator invented by Ernest Lawrence, which became essential in nuclear research.
- **Synchrotron Concept**: He proposed the idea of phase stability in charged particle beams, which was foundational to the development of the synchrotron, a key tool in high-energy physics.
- **Research Publications**: Authored and co-authored numerous scientific papers, particularly in the fields of nuclear and particle physics, contributing to the theoretical understanding of atomic nuclei.

## FAQs
### What is Edwin McMillan most famous for?
Edwin McMillan is most famous for discovering the element neptunium and for his early contributions to the understanding and naming of nuclear fission. His work laid the foundation for the discovery of heavier elements and advanced nuclear science.

### Where did Edwin McMillan study and work?
McMillan earned his undergraduate degree from the California Institute of Technology (Caltech) and completed his Ph.D. at Princeton University. He later worked at the University of California, Berkeley, and returned to Caltech, where he conducted much of his groundbreaking research.

### What awards did Edwin McMillan receive?
McMillan was awarded the Nobel Prize in Chemistry in 1951, shared with Glenn T. Seaborg, for discoveries in the chemistry of transuranium elements. He also received the National Medal of Science and the Atoms for Peace Award.

### What were Edwin McMillan's major scientific achievements?
His major achievements include the discovery of neptunium, coining the term "nuclear fission," and contributions to the development of particle accelerators like the synchrotron. These accomplishments significantly influenced nuclear and particle physics.

### Did Edwin McMillan contribute to any inventions or technologies?
Yes, McMillan's work on phase stability was crucial to the development of the synchrotron, a type of particle accelerator that became vital in high-energy physics research. His theoretical contributions helped shape modern accelerator technology.

## Why They Matter
Edwin McMillan's work fundamentally shaped the field of nuclear physics. His discovery of neptunium opened the door to the transuranium elements, expanding the periodic table. By coining and clarifying the concept of nuclear fission, he provided a framework for both peaceful and military applications of atomic energy. His contributions to particle acceleration technology, particularly the synchrotron, enabled future breakthroughs in high-energy physics. McMillan's influence extended to generations of physicists and chemists, and his work remains foundational in nuclear science and technology.

## Notable For
- **Discovery of Neptunium (1940)**: First transuranium element identified  
- **Nobel Prize in Chemistry (1951)**: Shared with Glenn T. Seaborg for transuranium discoveries  
- **Coining "Nuclear Fission"**: Helped define and popularize the term  
- **Synchrotron Development**: Pioneered the concept of phase stability in particle acceleration  
- **Member of Prestigious Academies**: National Academy of Sciences, American Academy of Arts and Sciences, American Philosophical Society  
- **Educator and Mentor**: Influenced students and researchers at Caltech and UC Berkeley  
- **Publications**: Authored and co-authored key scientific papers in nuclear and particle physics  

## Body

### Early Life and Education
Edwin Mattison McMillan was born on September 18, 1907, in Los Angeles, California. He pursued his undergraduate studies at the California Institute of Technology (Caltech), where he earned a Bachelor of Science in 1928. He then moved to Princeton University, completing his Ph.D. in 1932 with a dissertation on the "Energy Levels of the Tritium Nucleus."

### Career and Scientific Contributions
McMillan's career was primarily rooted in nuclear and particle physics. He joined the University of California, Berkeley, where he worked at the Berkeley Radiation Laboratory, a hub for nuclear research. His collaboration with scientists like Glenn Seaborg and Philip Abelson led to the discovery of neptunium in 1940, a pivotal moment in the study of transuranium elements.

#### Discovery of Neptunium
In 1940, Edwin McMillan and Philip Abelson identified neptunium, the first transuranium element. This discovery was significant as it confirmed the existence of elements beyond uranium on the periodic table, leading to the development of the actinide series.

#### Nuclear Fission
McMillan played a key role in defining and naming nuclear fission. His work helped clarify the process by which atomic nuclei split, releasing vast amounts of energy. This understanding was foundational to both nuclear power and nuclear weapons.

#### Particle Acceleration and the Synchrotron
McMillan proposed the concept of phase stability in charged particle beams, which was instrumental in the development of the synchrotron. This innovation allowed for the acceleration of particles to higher energies, enabling more precise and powerful experiments in nuclear and particle physics.

### Affiliations and Academic Roles
- **University of California, Berkeley**: McMillan spent much of his career at UC Berkeley, where he conducted groundbreaking research in nuclear physics and mentored numerous students.
- **California Institute of Technology (Caltech)**: He returned to Caltech at various points in his career, contributing to both research and education in physics.

### Awards and Recognition
- **Nobel Prize in Chemistry (1951)**: Shared with Glenn Seaborg for their discoveries in the chemistry of transuranium elements.
- **National Medal of Science**: Recognized for his contributions to nuclear science.
- **Atoms for Peace Award**: Acknowledged his work in advancing peaceful uses of atomic energy.

### Publications and Research
McMillan authored and co-authored numerous scientific papers, particularly in the fields of nuclear and particle physics. His research helped clarify the mechanisms of nuclear reactions and contributed to the theoretical underpinnings of modern atomic science.

### Legacy
Edwin McMillan's legacy is evident in the continued use of his theoretical and practical contributions in nuclear and particle physics. His work laid the foundation for modern atomic research, influencing everything from energy production to medical isotopes. His role in defining nuclear fission and discovering neptunium places him among the most significant figures in 20th-century physics.

## References

1. Integrated Authority File
2. NNDB
3. Find a Grave
4. [The Nobel Prize in Chemistry 1951. nobelprize.org](https://www.nobelprize.org/prizes/chemistry/1951/summary/)
5. [Table showing prize amounts. Nobel Foundation. 2019](https://www.nobelprize.org/uploads/2019/04/prize-amounts-2020.pdf)
6. [Source](https://achievement.org/our-history/golden-plate-awards/all-honorees/)
7. SNAC
8. Brockhaus Enzyklopädie
9. Munzinger Personen
10. Gran Enciclopèdia Catalana
11. nobelprize.org