Astrophysics & Particle Physics-APPC 2026

Atomic and Molecular Physics examines the basic properties and behavior of atoms and molecules, such as their structure, energy levels, and interactions. Atomic and Molecular Physics synthesizes quantum mechanics principles with experimental methods to analyze the microscopic phenomena that determine matter.Just as atomic physics experimenters study electron configurations, atomic energy levels, and transitions giving rise to spectral lines, spectroscopic techniques provide detailed information regarding atomic structure, magnetic and electric interactions, and hyperfine splitting.

These studies are also essential in the design of lasers, atomic clocks, and precision measurements. Molecular physics investigates chemical bonds, molecular vibrations, rotations, and electronic transitions and reveals information about molecular structure and dynamics. Methods such as infrared spectroscopy, Raman spectroscopy, and microwave spectroscopy enable researchers to interrogate molecular properties, reaction dynamics, and energy transfer processes.Molecular and atomic physics is also crucial in the physics of plasma, investigating collisions between ions, electrons, and neutral atoms in high-temperature settings. Understanding atomic and molecular phenomena is crucial to model stellar atmospheres, interstellar clouds, and laboratory plasma experiments.

Extrapolations occur in astrophysics, where atomic and molecular spectroscopy can identify elements and molecules in stars, galaxies, and the interstellar medium. These discoveries feed back into models for stellar evolution, star formation, and galactic chemical enrichment.The same research in atomic and molecular physics today encompasses quantum control, cold atoms, ultracold molecules, and precision tests of the basic laws of physics. Laboratory experimentation and computational techniques supplement theoretical models so that detailed investigations of quantum interactions become possible.

By studying the properties and behavior of atoms and molecules, this discipline gives one a basis from which to understand astrophysical processes, chemical reactions, and quantum phenomena, as well as bridge microscopic quantum laws and macroscopic physical observations.Atomic and molecular physics continues to be at the core of quantum technologies, spectroscopy, and understanding matter in the universe.