At the center of each atom in our bodies - and in the matter all around us - there is a nucleus. Atomic nuclei are made of protons and neutrons, collectively known as nucleons. Different combinations of protons and neutrons can give rise to a wide range of phenomena. These range from tightly bound nuclei that form the familiar elements of everyday life, to exotic fragile structures that decay while emitting radiation, and transient states that fall apart dripping nucleons. They even include the nuclear reactions that power the stars and drive the evolution of our universe.

Arriving at a comprehensive and predictive understanding of how such a wide range of phenomena emerges from the laws of quantum mechanics and the fundamental strong force among protons and neutrons is an overarching goal of nuclear physics. For a long time, a seemingly insurmountable obstacle towards achieving this goal was the disconnect between the microscopic treatment of the structure of nuclei as bound states of interacting nucleons and the theory used to model nuclear reactions.

This Early Career Award allowed me to make seminal contributions to the development of a unified understanding of the structure and low-energy reactions of light nuclei. It opened the way to the accurate microscopic description of thermonuclear reactions between light nuclei during the Big Bang and in the interior of our Sun.

Another major outcome of the project was a more fundamental understanding of the properties of halo nuclei, fragile bound states of one or two nucleons orbiting a tightly bound core at surprisingly extended distances. This foundational work was later extended to the treatment of even more complex exotic nuclei and reaction processes and inspired others to develop complementary techniques.  

I will be forever honored and grateful to have been the recipient of an Early Career Award.


Sofia Quaglioni is the Deputy Group Leader of the Nuclear Data and Theory Group in the Nuclear and Chemical Sciences Division at Lawrence Livermore National Laboratory (LLNL).


The Early Career Research Program provides financial support that is foundational to early career investigators, enabling them to define and direct independent research in areas important to DOE missions. The development of outstanding scientists and research leaders is of paramount importance to the Department of Energy Office of Science. By investing in the next generation of researchers, the Office of Science champions lifelong careers in discovery science.

For more information, please go to the Early Career Research Program.


Solving the Long‐Standing Problem of Low‐Energy Nuclear Reactions at the Highest Microscopic Level

This project aims to develop a comprehensive framework that will lead to a fundamental description of both structural properties and reactions of light nuclei in terms of constituent protons and neutrons interacting through nucleon‐nucleon and three‐nucleon forces. This is a long‐sought goal of nuclear theory that is now within reach as new promising techniques and the required computational power to implement them are becoming available.

This project will provide the research community with the theoretical and computational tools that will enable (1) an accurate prediction for the fusion reactions that power stars and Earth‐based fusion facilities; (2) an improved description of the spectroscopy of exotic nuclei, including light borromean systems; and (3) a fundamental understanding of the three‐nucleon force in nuclear reactions and nuclei at the drip line.


P. Navratil, S. Quaglioni, G. Hupin, C. Romero-Redondo, A. Calci, “Unified ab initio approaches to nuclear structure and reactions.” Physica Scripta 91, 053002 (2016). [DOI:10.1088/0031-8949/91/5/053002]

S. Baroni, P. Navratil, and S. Quaglioni, “Ab initio description of the exotic unbound 7He nucleus.” Physical Review Letters 110, 022505 (2013). [DOI:10.1103/PhysRevLett.110.022505]

S. Baroni, P. Navratil, and S. Quaglioni, “Unified ab initio approach to bound and unbound states: No-core shell model with continuum and its application to 7He.” Physical Review C 87, 034326 (2013). [DOI:10.1103/PhysRevC.87.034326]


Additional profiles of the Early Career Research Program award recipients can be found at https://www.energy.gov/science/listings/early-career-program

The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit www.energy.gov/science.

Sandra Allen McLean is a Communications Specialist in the Office of Science, Office of Communications and Public Affairs [email protected]

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