A century after the birth of quantum mechanics, advances in quantum science and technology continue. Transverse-momentum-dependent PDFs (TMD PDFs, or simply TMDs) offer a powerful way to probe the 3D structure of protons, neutrons, and nuclei, and to test quantum theory at its limits. In our fifth episode of “Stories Straight from the Heart of Matter,” we explore the internal structure of nucleons through TMDs with our expert, Elena Boglione from University of Turin.

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Further Reading

• The TMD Handbook offers a broad overview of TMDs, including their theoretical foundations, how they are used to interpret experimental data, and their role in modern nuclear physics research.
• Phenomenology of TMD parton distributions in Drell–Yan and Z⁰ boson production in a hadron-structure-oriented approach describes, in a clear and structured way, how physicists interpret high-energy collision data to learn about the internal motion of quarks inside protons.