Excitation is a research area within the field of physics that focuses on the processes and mechanisms by which energy is transferred to atoms, molecules, or particles, leading to a change in their electronic or vibrational states. This can occur through various means such as photon absorption, electron impact, or collisions with other particles. Excitation plays a crucial role in many areas of physics, including spectroscopy, plasma physics, and chemical dynamics. It is also essential for understanding the behavior of materials under different conditions, such as high temperatures or intense radiation. Researchers in this area study the fundamental principles underlying excitation processes and develop experimental and theoretical tools to investigate and control these processes for various applications.