revised 11/98

1999 PACS, 40. - 49.

Summary of Scheme

40. Electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics
41. Electromagnetism; Electron and Ion Optics
41.20.-q Applied classical electromagnetism
03.50.D Maxwell theory)
41.20.Cv Electrostatics; Poisson and Laplace equations, boundary-value problems
41.20.Gz Magnetostatics; magnetic shielding, magnetic induction, boundary- value problems
41.20.Jb Electromagnetic wave propagation; radiowave propagation (see also 84.40.C Radiowave and microwave propagation; for light propagation, see 42.25.B; for propagation in plasma, see 52.35.H; for ionospheric and magnetospheric propagation, see 94.20.B and 94.30.T)
41.50.+h X-ray beams and x-ray optics (see also 07.85.F in instruments)
41.60.-m Radiation by moving charges
41.60.Ap Synchrotron radiation (for synchrotron radiation instrumentation, see 07.85.Q)
41.60.Bq Cherenkov radiation
41.60.Cr Free-electron lasers (see also 52.75.M Free-electron devices)
41.75.-i Charged-particle beams
41.75.Ak Positive-ion beams
41.75.Cn Negative-ion beams
41.75.Fr Electron and positron beams
41.75.Ht Relativistic electron and positron beams
41.75.Jv Laser-driven acceleration (see also 52.40.N Laser-plasma interactions)
41.75.Lx Other advanced accelerator concepts
41.85.-p Beam optics (see also 07.77 Atomic, molecular, and charged particle sources and detectors, 29.27 Beams in particle accelerators)
41.85.Ar Beam extraction, beam injection
41.85.Ct Beam shaping, beam splitting
41.85.Ew Beam profile, beam intensity
41.85.Gy Chromatic and geometrical aberrations
41.85.Ja Beam transport
41.85.Lc Beam focusing and bending magnets, wiggler magnets, and quadrupoles (see also 07.55.D--in instruments, 85.70.N--in magnetic devices; for superconducting magnets, see 85.25.L)
41.85.Ne Electrostatic lenses, septa
41.85.Qg Beam analyzers, beam monitors, and Faraday cups
41.85.Si Beam collimators, monochromators
41.90.+e Other topics in electromagnetism; electron and ion optics (restricted to new topics in section 41)
42. Optics (for optical properties of gases, see 51.70; for optical properties of condensed matter, see 78)
42.15.-i Geometrical optics
42.15.Dp Wave fronts and ray tracing
42.15.Eq Optical system design
42.15.Fr Aberrations
42.25.-p Wave optics
42.25.Bs Wave propagation; transmission and absorption (for radiowave propagation, see 41.20.J and 84.40.C; for propagation in atmosphere, see 42.68.A; see also 52.40.D, N--in plasma physics)
42.25.Dd Wave propagation in random media
42.25.Fx Diffraction and scattering
42.25.Gy Edge and boundary effects; reflection and refraction
42.25.Hz Interference
42.25.Ja Polarization
42.25.Kb Coherence
42.25.Lc Birefringence
42.30.-d Imaging and optical processing
42.30.Kq Fourier optics
42.30.Lr Modulation and optical transfer functions
42.30.Ms Speckle and moire patterns
42.30.Rx Phase retrieval
42.30.Sy Pattern recognition
42.30.Tz Computer vision; robotic vision
42.30.Va Image forming and processing
42.30.Wb Image reconstruction; tomography
42.40.-i Holography
42.40.Eq Holographic optical elements; holographic gratings
42.40.Ht Hologram recording and read-out methods (see also 42.70.L Holographic recording materials; optical storage media)
42.40.Jv Computer-generated holograms
42.40.Kw Holographic interferometry; other holographic techniques (see also 07.60.L Interferometers)
42.40.Lx Diffraction efficiency, resolution, and other hologram characteristics
42.40.My Applications
42.40.Pa Volume holograms
42.50.-p Quantum optics (for lasers, see 42.55 and 42.60; see also 42.65 Nonlinear optics, 03.65 Quantum mechanics)
42.50.Ar Photon statistics and coherence theory
42.50.Ct Quantum description of interaction of light and matter; related experiments
42.50.Dv Nonclassical field states; squeezed, antibunched, and sub-Poissonian states; operational definitions of the phase of the field; phase measurements
42.50.Fx Cooperative phenomena; superradiance and superfluorescence
42.50.Gy Effects of atomic coherence on propagation, absorption, and amplification of light
42.50.Hz Strong-field excitation of optical transitions in quantum systems; multi-photon processes; dynamic Stark shift (for multiphoton ionization and excitation of atoms and molecules, see 32.80.R, and 33.80.R, respectively)
42.50.Lc Quantum fluctuations, quantum noise, and quantum jumps
42.50.Md Optical transient phenomena: quantum beats, photon echo, free- induction decay, dephasings and revivals, and optical nutation, and self-induced transparency
***** Dynamics of nonlinear optical systems; optical instabilities, optical chaos, and optical spatio temporal dynamics, see 42.65.S
***** Optical solitons; nonlinear guided waves, see 42.65.T
42.50.Vk Mechanical effects of light on atoms, molecules, electrons, and ions (see also 32.80.P and 33.80.P Optical cooling and trapping of atoms and molecules)
***** Optical tests of fundamental laws and forces, see 12.20.F Experimental tests in quantum electrodynamics and 03.65.B Theory of measurements in quantum mechanics
42.55.-f Lasers
42.55.Ah General laser theory
42.55.Ks Chemical lasers (for chemical laser kinetics, see 82.40.T)
42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.55.Mv Dye lasers
42.55.Px Semiconductor lasers; laser diodes
42.55.Rz Doped-insulator lasers and other solid state lasers
42.55.Sa Microcavity and microdisk lasers
42.55.Vc X- and gamma-ray lasers
42.55.Wd Fiber lasers
42.55.Xi Diode-pumped lasers
42.55.Ye Raman lasers (see also 42.65.D Stimulated Raman scattering; CARS)
***** Free-electron lasers, see 41.60.C
42.60.-v Laser optical systems: design and operation
42.60.By Design of specific laser systems
42.60.Da Resonators, cavities, amplifiers, arrays, and rings
42.60.Fc Modulation, tuning, and mode locking
42.60.Gd Q-switching
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation
42.60.Lh Efficiency, stability, gain, and other operational parameters
42.60.Mi Dynamical laser instabilities; noisy laser behavior
42.60.Pk Continuous operation
42.60.Rn Relaxation oscillations and long pulse operation
***** Ultrashort pulse generation, see 42.65.T
***** Dynamics of nonlinear optical systems, see 42.65.S
42.62.-b Laser applications (for LIDAR, see 42.79.Q)
42.62.Be Biological and medical applications
42.62.Cf Industrial applications
42.62.Eh Metrological applications (see also 06.20 Metrology, 06.30 Measurements common to several branches of physics and astronomy)
42.62.Fi Laser spectroscopy
42.65.-k Nonlinear optics
42.65.An Optical susceptibility, hyperpolarizability (see also 33.15.M Electric and magnetic moments, polarizability and magnetic susceptibility of molecules)
42.65.Dr Stimulated Raman scattering; CARS
42.65.Es Stimulated Brillouin and Rayleigh scattering
42.65.Hw Phase conjugation, optical mixing, and photorefractive effect
42.65.Jx Beam trapping, self-focusing, and thermal blooming
42.65.Ky Harmonic generation and frequency conversion (see also 42.79.N Optical frequency converters)
42.65.Pc Optical bistability, multistability, and switching (see also 42.60.G Switching and pulsing; 42.79.T Optical computers, logic elements, interconnects, switches; neural networks)
42.65.Re Ultrafast processes; optical pulse generation and pulse compression (see also 42.60.G Switching and pulsing)
42.65.Sf Dynamics of nonlinear optical systems; optical instabilities, optical chaos, and complexity, and optical spatio-temporal dynamics
42.65.Tg Optical solitons; nonlinear guided waves (for solitons in fibers, see 42.81.D)
42.65.Wi Nonlinear waveguides
42.65.Yj Optical parametric oscillators and amplifiers
42.66.-p Physiological optics
42.66.Ct Anatomy and optics of eye
42.66.Ew Physiology of eye; optic-nerve structure and function
42.66.Lc Vision: light detection, adaptation, and discrimination
42.66.Ne Color vision: color detection, adaptation, and discrimination
42.66.Qg Scales for light and color detection
42.66.Si Psychophysics of vision, visual perception; binocular vision
42.68.-w Atmospheric optics
42.68.Ay Propagation, transmission, attenuation, and radiative transfer (see also 92.60.T Interaction of atmosphere with electromagnetic waves; propagation)
42.68.Bz Atmospheric turbulence effects (see also 92.60.E Convection, turbulence, and diffusion)
42.68.Ca Spectral absorption by atmospheric gases (see also 94.10.G Absorption and scattering of radiation)
42.68.Ge Effects of clouds and water (see also 92.60.J Water in the atmosphere, 92.60.N Cloud physics)
42.68.Jg Effects of aerosols (see also 92.60.M Particles and aerosols)
42.68.Kh Effects of air pollution (see also 92.60.S Air quality and air pollution)
42.68.Mj Scattering, polarization (see also 94.10.G Absorption and scattering of radiation)
42.68.Sq Image transmission and formation
42.68.Wt Remote sensing, LIDAR, and adaptive systems
42.70.-a Optical materials (for materials science, see 81; for optical properties of bulk materials, see 78.20)
42.70.Ce Glasses, quartz
42.70.Df Liquid crystals (for structure of liquid crystals, see 61.30)
42.70.Gi Light-sensitive materials
42.70.Hj Laser materials
42.70.Jk Polymers and organics
42.70.Km Infrared transmitting materials
42.70.Ln Holographic recording materials; optical storage media
42.70.Mp Nonlinear optical crystals (see also 77.84 Dielectric, piezoelectric, and ferroelectric materials)
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials
42.70.Qs Photonic bandgap materials
42.72.-g Optical sources and standards (for lasers, see 42.55; see also 07.57.H in instruments)
42.72.Ai Infrared sources
42.72.Bj Visible and ultraviolet sources
42.79.-e Optical elements, devices, and systems (for integrated optics, see 42.82; for fiber optics see 42.81)
***** Optical instruments, equipment and techniques, see 07.60 and 07.57
***** Optical spectrometers, see 07.57.T and 07.60.R
***** Photography, photographic instruments and techniques, see 07.68
***** Magnetooptical devices, see85.70.S
42.79.Ag Apertures, collimators
42.79.Bh Lenses, prisms, and mirrors
42.79.Ci Filters, zone plates, and polarizers
42.79.Dj Gratings (for holographic gratings, see 42.40.E)
42.79.Ek Solar collectors and concentrators (see also 84.60.J Solar cells and arrays)
42.79.Fm Reflectors, beam splitters, and deflectors
42.79.Gn Optical waveguides and couplers (for fiber waveguides and waveguides in integrated optics see 42.81.Q and 42.82.E, respectively)
42.79.Hp Optical processors, correlators, and modulators
42.79.Jq Acousto-optical devices (see also 43.38.Z - in acoustics appendix)
42.79.Kr Display devices, liquid-crystal devices (see also 85.60.P Display systems)
42.79.Ls Scanners, image intensifiers, and image converters (see also 85.60 Photoelectric and optoelectronic devices and systems)
42.79.Mt Schlieren devices
42.79.Nv Optical frequency converters
42.79.Pw Imaging detectors and sensors (see also 85.60.G Photodetectors)
42.79.Qx Range finders, remote sensing devices; laser Doppler velocimeters, SAR, and LIDAR (see also 42.68.W Remote sensing; LIDAR, and adaptive systems)
42.79.Ry Gradient-index (GRIN) devices (for fiber GRIN devices, see 42.81.H)
42.79.Sz Optical communication systems, multiplexers, and demultiplexers
42.79.Ta Optical computers, logic elements, interconnects, switches; neural networks
42.79.Vb Optical storage systems, optical disks (see also 42.40.H Hologram recording and readout methods)
42.79.Wc Optical coatings
42.81.-i Fiber optics
***** Fiber-optic instruments, see 07.60.V 42.81.Bm Fabrication, cladding, and splicing
42.81.Cn Fiber testing and measurement of fiber parameters
42.81.Dp Propagation, scattering, and losses; solitons
42.81.Gs Birefringence, polarization
42.81.Ht Gradient-index (GRIN) fiber devices
42.81.Pa Sensors, gyros
42.81.Qb Fiber waveguides, couplers, and arrays
42.81.Wg Other fiber-optical devices (for fiber lasers, see 42.55.W)
42.82.-m Integrated optics
42.82.Bq Design and performance testing of integrated-optical systems
42.82.Cr Fabrication techniques; lithography, pattern transfer (see also 85.40 Microelectronics: LSI, VLSI, ULSI; integrated circuit fabrication technology)
42.82.Ds Interconnects, including holographic interconnects (see also 42.79.T Optical computers, logic elements, interconnects, switches; neural networks)
42.82.Et Waveguides, couplers, and arrays (for fiber waveguides see 42.81.Q)
42.82.Fv Hybrid systems
42.82.Gw Other integrated-optical elements and systems
42.86.+b Optical workshop techniques
42.87.-d Optical testing techniques
42.87.Bg Phase shifting interferometry (see also 07.60.L Interferometers)
42.88.+h Radiation effects on optical elements, devices, and systems
42.90.+m Other topics in optics (restricted to new topics in section 42)
43. Acoustics (for more detailed headings, see Appendix to 43)
43.20.+g General linear acoustics (see also
03.40.K Waves and wave propagation: general mathematical aspects)
43.25.+y Nonlinear acoustics
43.28.+h Aeroacoustics, atmospheric sound (see also 92.60. Meteorology)
43.30.+m Underwater sound (see also 92.10.V - in physics of oceans)
43.35.+d Ultrasonics, quantum acoustics, and physical effects of sound
***** Phonons in crystal lattices, see 63.20
***** Acoustical properties of rocks and minerals, see 91.60.L
***** Sound waves in plasma, see 52.35.D
***** Low-temperature acoustics and sound in liquid helium, see 67
***** Acoustical properties of solids, see 62.65; for ultrasonic relaxation, see 62.80
***** Acoustic properties of thin films, see 68.60.B
***** Surface waves in liquids and solids, see 68.10 and 68.35.G
***** Acoustoelectric effects, see 72.50 and 73.50.R
***** Magnetoacoustic effects, oscillations, and resonance, see 72.55, 73.50.R, and 75.80
***** Acoustic holography, see 43.60; for acoustooptical effects, see 78.20.H
43.38.+n Transduction; acoustical devices for the generation and reproduction of sound
43.40.+s Structural acoustics and vibration
43.50.+y Noise: its effects and control
43.55.+p Architectural acoustics
43.58.+z Acoustical measurements and instrumentation
43.60.+d Acoustic signal processing
43.64.+r Physiological acoustics
***** Biological effects of sound and ultrasound, see 87.50.K 43.66.+y Psychological acoustics
43.70.+i Speech production
43.71.+m Speech perception
43.72.+q Speech processing and communication systems
43.75.+a Music and musical instruments
43.80.+p Bioacoustics
43.90.+v Other topics in acoustics (restricted to new topics in section 43)
44. Heat transfer
44.05.+e Analytical and numerical techniques
44.10.+i Heat conduction (see also
66.60 and 66.70 in transport properties of condensed matter)
44.15.+a Channel and internal heat flow
44.20.+b Boundary layer heat flow
44.25.+f Natural convection (see also 47.27.T Convection and heat transfer in fluid dynamics)
44.27.+g Forced convection
44.30.+v Heat flow in porous media
44.35.+c Heat flow in multiphase systems
44.40.+a Thermal radiation
44.90.+c Other topics in heat transfer (restricted to new topics in section 44)
45. Classical mechanics of discrete systems
45.05.+x General theory of classical mechanics of discrete systems
45.10.-b Computational methods in classical mechanics (see also
02.70 Computational techniques in mathematical methods in physics)
45.10.Db Variational and optimization methods
45.10.Hj Perturbation and fractional calculus methods
45.10.Na Geometrical and tensorial methods
45.20.-d Formalisms in classical mechanics
45.20.Dd Newtonian mechanics
45.20.Jj Lagrangian and Hamiltonian mechanics
45.30.+s General linear dynamical systems (for nonlinear dynamical systems, see 05.45)
45.40.-f Dynamics and kinematics of rigid bodies
45.40.Cc Rigid body and gyroscope motion
45.40.Gj Ballistics (projectiles; rockets)
45.40.Ln Robotics
45.50.-j Dynamics and kinematics of a particle and a system of particles
45.50.Dd General motion
45.50.Jf Few- and many-body systems
45.50.Pk Celestial mechanics (see also 95.10.C in fundamental astronomy)
45.50.Tn Collisions
45.70.-n Granular systems (see also 05.65 Self-organized systems)
45.70.Cc Static sandpiles; granular compaction
45.70.Ht Avalanches
45.70.Mg Granular flow: mixing, segregation and stratification
45.70.Qj Pattern formation
45.70.Vn Granular models of complex systems; traffic flow
45.80.+r Control of mechanical systems (see also 46.60 Measurement methods and techniques in continuum mechanics of solids)
45.90.+t Other topics in classical mechanics of discrete systems (restricted to new topics in section 45)
46. Continuum mechanics of solids (see also 83.10.F in rheology)
46.05.+b General theory of continuum mechanics of solid
aspects, 95.10.C Celestial mechanics)
46.15.-x Computational methods in continuum mechanics (see also 02.70 Computational techniques in mathematical methods in physics)
46.15.Cc Variational and optimizational methods
46.15.Ff Perturbation and complex analysis methods
46.25.-y Static elasticity
46.25.Cc Theoretical studies
46.25.Hf Thermoelasticity and electromagnetic elasticity (electroeleasticity, magnetoelasticity)
46.32.+x Static buckling and instability
46.35.+z Viscoelasticity, plasticity, viscoplasticity (see also 83.50.B,N in rheology)
46.40.-f Vibrations and mechanical waves (see also 43.40 Structural acoustics and vibration; 62.30 in mechanical properties of solids)
46.40.Cd Mechanical wave propagation (including diffraction, scattering, and dispersion)
46.40.Ff Resonance, damping and dynamic stability
46.40.Jj Aeroelasticity and hydroelasticity
46.50.+a Fracture mechanics, fatigue and cracks (see also 62.20.M in mechanical properties of solids)
46.55.+d Tribology and mechanical contacts (see also 81.40.P Friction, lubrication and wear in materials science; 62.20.Q in mechanical properties of solids)
46.65.+g Random phenomena and media (see also 05.40 in statistical physics, thermodynamics and nonlinear dynamical systems)
46.70.-p Application of continuum mechanics to structures
46.70.De Beams, plates and shells
46.70.Hg Membranes, rods and strings
46.70.Lk Other structures
46.80.+j Measurement methods and techniques in continuum mechanics of solids (see also 07.10 Mechanical instruments, equipment, and techniques)
46.90.+s Other topics in continuum mechanics of solids (restricted to new topics in section 46)
47. Fluid Dynamics (for fluid dynamics of quantum fluids, see 67; see also 83 Rheology)
47.10.+g General theory (see also 83.10 in rheology)
47.11.+j Computational methods in fluid dynamics (see also 83.85.P Flow computation; 02.70 - in mathematical methods in physics)
47.15.-x Laminar flows
47.15.Cb Laminar boundary layers
47.15.Fe Stability of laminar flows
47.15.Gf Low-Reynolds-number (creeping) flows
47.15.Hg Potential flows
47.15.Ki Inviscid flows with vorticity
47.15.Pn Laminar suspensions
47.15.Rq Laminar flows in cavities
47.17.+e Mechanical properties of fluids (see also 62.10 Mechanical properties of liquids)
47.20.-k Hydrodynamic stability
47.20.Bp Buoyancy-driven instability
47.20.Cq Inviscid instability
47.20.Dr Surface-tension-driven instability
47.20.Ft Instability of shear flows
47.20.Gv Viscous instability
47.20.Hw Morphological instability; phase changes (see also 64 Equations of state, phase equilibria, and phase transitions)
47.20.Ky Nonlinearity (including bifurcation theory)
47.20.Lz Secondary instability
47.20.Ma Interfacial instability
47.20.Pc Receptivity
***** Chaotic phenomena, see 47.52 and 05.45
47.27.-i Turbulent flows, convection, and heat transfer
47.27.Ak Fundamentals
47.27.Cn Transition to turbulence
47.27.Eq Turbulence simulation and modeling
47.27.Gs Isotropic turbulence; homogeneous turbulence
47.27.Jv High-Reynolds-number turbulence
47.27.Lx Wall-bounded thin shear flows
47.27.Nz Boundary layer and shear turbulence
47.27.Pa Thick shear flows
47.27.Qb Turbulent diffusion
47.27.Rc Turbulence control
47.27.Sd Noise (turbulence generated)
47.27.Te Convection and heat transfer (see also 44.25 in heat transfer)
47.27.Vf Wakes
47.27.Wg Jets
47.32.-y Rotational flow and vorticity
47.32.Cc Vortex dynamics
47.32.Ff Separated flows
47.35.+i Hydrodynamic waves
47.37.+q Hydrodynamic aspects of superfluidity (see also 67.40.H and 67.57.D - in quantum fluids and solids)
47.40.-x Compressible flows; shock and detonation phenomena (see also 28.70 Nuclear explosions, 52.35.T Shock waves in plasma, 83.50.T--in rheology, 43.25.C, 43.28.M and 43.40.J--in acoustics appendix)
47.40.Dc General subsonic flows
47.40.Hg Transonic flows
47.40.Ki Supersonic and hypersonic flows
47.40.Nm Shock-wave interactions and shock effects
47.45.-n Rarefied gas dynamics
47.45.Dt Free molecular flows
47.45.Gx Slip flows
47.45.Nd Accommodation
47.50.+d Non-Newtonian fluid flows (see also 83.50 Deformation, material flow)
47.52.+j Chaos (see also 05.45 Nonlinear dynamics and nonlinear dynamical systems; 83.50.W Chaotic flows; drag reduction)
47.53.+n Fractals
47.54.+r Pattern selection; pattern formation
47.55.-t Nonhomogeneous flows
47.55.Bx Cavitation
47.55.Dz Drops and bubbles
47.55.Hd Stratified flows
47.55.Kf Multiphase and particle-laden flows
47.55.Mh Flows through porous media (for heat transfer in porous media, see 44.30)
47.60.+i Flows in ducts, channels, nozzles, and conduits (see also 83.10 and 83.50 - in rheology)
***** Biological fluid dynamics, see 87.19.T
47.62.+q Flow control
47.65.+a Magnetohydrodynamics and electrohydrodynamics (for MHD in plasma, see 52.30)
47.70.-n Reactive, radiative, or nonequilibrium flows
47.70.Fw Chemically reactive flows (see also 83.80.J Chemically reactive materials)
47.70.Mc Radiation gas dynamics
47.70.Nd Nonequilibrium gas dynamics
47.75.+f Relativistic fluid dynamics (for astrophysical aspects,see 95.30.L)
47.80.+v Instrumentation for fluid dynamics (see also 83.85 - in rheology; 07.30 Vacuum apparatus and techniques)
47.90.+a Other topics in fluid dynamics (restricted to new topics in section 47)