Stellar nucleosynthesis is the process by which elements are created within stars by combining the protons and neutrons together from the nuclei of lighter elements. All of the atoms in the universe began as hydrogen. Fusion inside stars transforms hydrogen into helium, heat, and radiation. Mark Whittle University of Virginia . Lecture 7: "Basics of Star Formation and Stellar Nucleosynthesis" Outline 1. Nuclear fusion is an atomic reaction that fuels stars. Formation of elements in stars 2. Phases of star-formation 4. Evolution of stars. The slow neutron-capture process, or s-process, is a series of reactions in nuclear astrophysics that occur in stars, particularly AGB stars.The s-process is responsible for the creation (nucleosynthesis) of approximately half the atomic nuclei heavier than iron.. Four decades ago the seminal idea that essentially all of the elements were made by thermonuclear burning in stars (stellar nucleosynthesis) was codified (1, 2).Later, astronomical observations (3, 4) suggested that the elements were formed by some other process early in cosmological history, perhaps in the Big Bang itself.Ironically, existing analyses on Xe and Ne in … Injection of new elements into ISM 3. In the center of stars, atoms are taken apart by tremendous atomic collisions that alter the atomic structure and release an enormous amount of energy. Heavier elements are created in different types of stars as they die or explode. In the s-process, a seed nucleus undergoes neutron capture to form an isotope with one higher atomic mass. Nuclear Fusion and Nucleosynthesis Stars are giant nuclear reactors. This makes stars hot and bright. Contents Preface v Physical and astronomical constants vi 1 Introduction 1 2 Thermonuclear reactions 9 3 Big Bang nucleosynthesis 23 4 Hydrostatic nucleosynthesis in stars (A <56) 35