Nuclear Data 101 Lecture Series:
Reactions on Unstable Nuclei
Chairs: J. Batchelder (UC Berkeley), J. Despotopulos (LLNL), H-Y. Lee (LANL), G. Severin (MSU/NSCL)
Session Summary: Astrophysical nucleosynthesis, novel energy reactor technologies, and nuclear security applications simulate extreme environments where reactions on unstable nuclei can occur and where data are limited. New opportunities for experimental measurements and theoretical capabilities are on the horizon, providing important cross section constraints and potentially reducing uncertainties in these applications. In this session we will focus on reaction data for unstable isotopes with decay half-lives of hours to days. New experimental techniques with indirect and direct cross-section methods and theoretical inputs will be covered, as well as evaluation methods for the potentially complex reaction pathways.
Nuclear Data for High Energy Ion Interactions and Secondary Particle Production
Chairs: K.LaBel (KBR Wyle/SSAI), M. Smith (ORNL), R. Vogt (LLNL/UC Davis)
Session Summary: The Galactic Cosmic Ray background covers a wide energy range, peaking at several hundred MeV/nucleon, but extending up to and beyond 10 GeV/nucleon. The interaction of these particles with spacecraft materials and occupants creates a large and complex cascade that presents challenges to modeling, especially in the absence of measured data covering the entire energy range. In this session we will identify the improvements required in all components of the nuclear data pipeline to enable safe space exploration.
Neutrons as Secondary Particles and Their Interactions with Matter
Chairs: L. Heilbronn (UT Knoxville), N. Hertel (ORNL), T. Slaba (NASA)
Session Summary: Energetic neutrons can impart significant dose to both humans involved in space exploration and the electronics they rely on. They also play an important role in understanding materials damage in fusion and fast fission reactors and in the design of missile defense systems. Lastly, fast neutrons can be used to explore elemental identification in extraterrestrial bodies. In this session we will explore the nuclear data dependencies in these applications, paying special attention to crosscutting needs.
Photon Reactions and Transport
Chairs: B. Beck (LLNL), C. Howell (TUNL/Duke), T. Kawano (LANL), C. Miller (DHS)
Session Summary: In this session we will be discussing high-energy x-ray and gamma-ray data used in diagnostic and imaging applications. Of particular interest are photon-induced nuclear reactions such as photoabsorption, photoneutron, and photofission. Aspects of the photon data throughout the nuclear data pipeline will be covered including experiments, theory and evaluation, data library production, and use in applications simulations.
Stopping powers, energy deposition and dose
Chairs: L. Bernstein (UC Berkeley/LBNL), P. Griffin (SNL), M. Kruse (LLNL), T. Turflinger (Aero)
Session Summary: Heavy-ions and beta-particles from nuclear reactions induced by the Galactic Cosmic Ray background and Coronal Mass Ejections lead to large local energy deposition (e.g., dose), particularly in the vicinity of the Bragg Peak. However, significant uncertainties exist in charged-particle stopping powers, introducing difficulties in the design of spacecraft shielding, fission fragment detectors, isotope production and ion-beam therapy. In this session we will work to identify needs and develop a plan to improve the modeling of charged-particle stopping powers over a broad range of energies and masses.
Nuclear Data adjustments and Impact on Applications
Chairs: D. Neudecker (LANL), A. Lewis (NNL), R. Casperson (LLNL)
Session Summary: The adjustment process is a key step for many nuclear data users. Through this process they gain optimized nuclear data libraries that encompass knowledge from basic nuclear physics augmented with validation experiments tailored to represent their target application. Adjustment not only reliably reduces the application’s economic and safety margins but at the same time provides a library that can be used with confidence in limited simulations. CSEWG currently provides a “general-purpose” library built upon basic nuclear physics knowledge. Here, we will explore (a) which user groups use adjustment and what lessons have they learned, (b)which other users would benefit from adjusted libraries, (c) the benefits of adjustment, (d) the major stumbling blocks encountered in adjustment and how they can be mitigated, (e) how past integral data can be leveraged, and (f) what tools are needed for the entire adjustment process. The goal of this session is to identify cross-cutting tools needed by multiple programs and the best pathways forward to provide them.