Interaction of X-rays and Neutrons with Materials | NNSS 2025 скачать в хорошем качестве

Interaction of X-rays and Neutrons with Materials | NNSS 2025

Interaction of X-rays and Neutrons with Materials Presented by Roger Pynn 1st National Neutron Scattering School, 2025 Oak Ridge National Laboratory (ORNL) In this lecture, Roger Pynn examines how x-rays and neutrons interact with matter and explains the physical principles that distinguish these two probes. The presentation establishes how differences in scattering mechanisms lead to complementary sensitivities to atomic number, magnetic structure, and light elements. Pynn outlines the fundamental interactions underlying x-ray scattering from electron clouds and neutron scattering from atomic nuclei and magnetic moments. The lecture discusses scattering lengths, cross sections, absorption effects, and how these properties influence contrast, penetration depth, and experimental design. Emphasis is placed on understanding how probe–matter interactions determine what structural and magnetic information can be extracted. By comparing x-ray and neutron interactions side by side, the session highlights why neutrons are uniquely suited for studies of hydrogen, isotope contrast variation, and magnetism, while x-rays excel in other regimes. The lecture reinforces the importance of choosing the appropriate probe based on the scientific question and material system under investigation. Learn more about neutron science at ORNL: https://neutrons.ornl.gov Learn about the National Neutron Scattering School at ORNL: https://neutrons.ornl.gov/nns