**1999 PACS, 40. - 49.
**

**
Summary of Scheme
**

40. FUNDAMENTAL AREAS OF PHENOMENOLOGY (INCLUDING APPLICATIONS)

**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)