Physics
A00 - GENERAL
A01 - Communication, education, history, and philosophy
A02 - Mathematical methods in physics
A03 - Classical and quantum physics; mechanics and fields
A04 - Relativity and gravitation
A05 - Statistical physics and thermodynamics
A06 - Measurement science, general laboratory techniques, and instrumentation systems
A07 - Specific instrumentation and techniques of general use in physics
A10 - THE PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
A11 - General theory of fields and particles
A12 - Specific theories and interaction models; particle systematics
A13 - Specific reactions and phenomenology
A14 - Properties of specific particles and resonances
A20 - NUCLEAR PHYSICS
A21 - Nuclear structure
A23 - Radioactivity and electromagnetic transitions
A24 - Nuclear reactions and scattering: general
A25 - Nuclear reactions and scattering: specific reactions
A27 - Properties of specific nuclei listed by mass ranges
A28 - Nuclear engineering and nuclear power studies
A29 - Experimental methods and instrumentation for elementary-particle and nuclear physics
A30 - ATOMIC AND MOLECULAR PHYSICS
A31 - Theory of atoms and molecules
A32 - Atomic spectra and interactions with photons
A33 - Molecular spectra and interactions with photons
A34 - Atomic and molecular collision processes and interactions
A35 - Properties of atoms and molecules; instruments and techniques
A36 - Studies of special atoms and molecules
A40 - CLASSICAL AREAS OF PHENOMENOLOGY
A41 - Electricity and magnetism; fields and charged particles
A42 - Optics
A43 - Acoustics
A44 - Heat flow, thermal and thermodynamic processes
A46 - Mechanics, elasticity, rheology
A47 - Fluid dynamics
A50 - FLUIDS, PLASMAS AND ELECTRIC DISCHARGES
A51 - Kinetic and transport theory of fluids; physical properties of gases
A52 - The physics of plasmas and electric discharges
A60 - CONDENSED MATTER: STRUCTURE, THERMAL AND MECHANICAL PROPERTIES
A61 - Structure of liquids and solids; crystallography
A62 - Mechanical and acoustic properties of condensed matter
A63 - Lattice dynamics and crystal statistics
A64 - Equations of state, phase equilibria, and phase transitions
A65 - Thermal properties of condensed matter
A66 - Transport properties of condensed matter (nonelectronic)
A67 - Quantum fluids and solids; liquid and solid helium
A68 - Surfaces and interfaces; thin films and whiskers
A70 - CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES
A71 - Electron states
A72 - Electronic transport in condensed matter
A73 - Electronic structure and electrical properties of surfaces, interfaces, and thin films
A74 - Superconductivity
A75 - Magnetic properties and materials
A76 - Magnetic resonances and relaxation in condensed matter; Mössbauer effect
A77 - Dielectric properties and materials
A78 - Optical properties and condensed matter spectroscopy and other interactions of matter with particles and radiation
A79 - Electron and ion emsission by liquids and solids; impact phenomena
A80 - CROSS-DISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY
A81 - Materials science
A82 - Physical chemistry
A86 - Energy research and environmental science
A87 - Biophysics, medical physics, and biomedical engineering
A90 - GEOPHYSICS, ASTRONOMY AND ASTROPHYSICS
A91 - Solid Earth physics
A92 - Hydrospheric and lower atmospheric physics
A93 - Geophysical observations, instrumentation, and techniques
A94 - Aeronomy, space physics, and cosmic rays
A95 - Fundamental astronomy and astrophysics, instrumentation and techniques and astronomical observations
A96 - Solar system
A97 - Stars
A98 - Stellar systems; Galactic and extragalactic objects; Universe