Changes made in the 1995 PACS Scheme

• Deleted categories
• New categories
• Modified categories

Deleted PACS Categories from 1995 Edition

06.20.Hq Measurement standards
USE 06.20.F
06.30.Lz Measurement of basic electromagnetic quantities
USE 07.50.- and/or 07.55.-
06.50.-x Data handling and computation
USE 07.05.-
06.50.Dc Data gathering, processing, and recording; data displays (including digital techniques)
USE 07.05.H, K or R
06.50.Mk Computing devices and techniques
USE 07.05.B
06.70.-h General instrumentation
USE 07.07.-
06.70.Dn Sensing and detecting devices
USE 07.07.D
06.70.Ep Testing equipment
USE 07.07.Y
06.70.Hs Display, recording, and indicating instruments
USE 07.07.H
06.70.Mx Transducers
USE 07.07.M
06.70.Td Servo and control devices
USE 07.07.T
07.10.+i Mechanical instruments and measurement methods
USE 07.10.-
07.25.+f Hygrometry
USE 07.07.V
07.50.+f Electrical instruments and techniques
USE 07.50.-
07.55.+x Magnetic instruments and techniques
USE 07.55.-
07.58.+g Magnetic resonance spectrometers, auxiliary instruments, and techniques
USE 07.57.P
07.62.+s Detection of radiation (bolometers, photoelectric cells, infrared and submillimeter wave detection)
USE 07.57.K
07.65.-b Optical spectroscopy and spectrometers
USE 07.60.R and 07.57.T
07.65.Eh Visible and ultraviolet spectroscopy and spectrometers
USE 07.60.R
07.65.Gj Infrared spectroscopy and spectrometers
USE 07.57.T
07.77.+p Particle beam production and handling; targets
USE 07.77.-
07.80.+x Electron and ion microscopes and spectrometers; techniques
USE 07.78.+
07.85.+n X- and gamma-ray instruments and techniques
USE 07.85.-
31.15.+q General mathematical and computational developments
USE 31.15.-
31.20.-d Specific calculations and results
USE 31.15.-
31.20.Di Complete ab initio calculations (exact or nearly exact calculations on small species)
USE 31.15.A
31.20.Ej Ab initio MO calculations
USE 31.15.A and 31.15.N
31.20.Gm Other accurate, or nearly ab initio calculations (MNDO method, SAMO method, etc.)
USE 31.15.A
31.20.Lr Statistical model calculations (Thomas-Fermi and Thomas-Fermi-Dirac models)
USE 31.15.B
31.20.Nt Semi-empirical NDO calculations (CNDO, INDO, MINDO, PCILO methods, etc.)
USE 31.15.C
31.20.Pv Other semiempirical calculations (Hueckel, generalized Hueckel, PPP methods, etc.)
USE 31.15.C
31.20.Rx Valence bond calculations (ab initio or not)
USE 31.15.R
31.20.Sy Density functional methods (local density approximation, local spin density approximation), X[subon]alpha[suboff] methods
USE 31.15.E
31.20.Tz Electron correlation and CI calculations
USE 31.25.-
31.20.Wb Empirical methods (nonquantum methods for conformations, as Wiberg method, Westheimer method, etc.)
USE 31.15.C
33.10.-n Calculation of molecular spectra
USE 31.15.- and 33.20.-
33.10.Cs Calculational methods (including new theoretical techniques and applications of group theory)
USE 31.20.-
33.10.Ev Rotational analysis
USE 33.20.S
33.10.Gx Vibrational analysis
USE 33.20.T
33.10.Jz Vibration-rotational analysis
USE 33.20.V
33.10.Lb Vibronic, rovibronic, and rotation-electron-spin interactions
USE 33.20.W
33.25.-j Nuclear magnetic resonance (NMR) and relaxation
USE 33.25.+
33.25.Bn Relaxation phenomena
USE 33.25.+
33.25.Dq Chemical shifts
USE 33.25.+
33.25.Fs Nuclear spin interactions and quadrupole effects
USE 33.25.+
33.25.Hv Chemically induced dynamic nuclear polarization (CIDNP)
USE 33.25.+
33.30.+a Nuclear quadrupole resonance (NQR)
USE 33.25.+
33.35.-q Electron paramagnetic resonance (EPR) and relaxation
USE 33.35.+
33.35.Cv Relaxation phenomena
USE 33.35.+
33.35.Ex EPR spectra
USE 33.35.+
33.35.Gz Chemically induced dynamic electron polarization (CIDEP)
USE 33.35.+
33.40.-e Multiple resonances
USE 33.40.+
33.40.Ci Double nuclear magnetic resonance (DNMR), electron-nuclear double resonance (ENDOR), and electron double resonance (ELDOR)
USE 33.40.+
33.40.Hp Microwave optical double resonance spectroscopy (MODOR) and phosphorescence microwave double resonance spectroscopy (PMDR)
USE 33.40.+
33.40.Ta Other multiple resonances
USE 33.40.+
34.40.+n Elastic scattering of atoms and molecules
USE 34.50.-
35. Experimentally derived information on atoms and molecules; instrumentation and techniques
35.10.-d Atoms
USE 32.10.-
35.10.Bg Atomic masses, mass spectra, abundances, and isotopes
USE 32.10.B
35.10.Di Electric and magnetic moments, polarizability
USE 32.10.D
35.10.Fk Fine- and hyperfine-structure constants
USE 32.10.F
35.10.Hn Ionization potentials, electron affinities
USE 32.10.H
35.10.Wb Weak interactions
USE 32.80.Y
35.20.-i Molecules
USE 33.15.-
35.20.Bm General molecular conformation and symmetry; stereochemistry
USE 33.15.B
35.20.Dp Interatomic distances and angles
USE 33.15.D
35.20.Gs Bond strengths, dissociation energies, hydrogen bonding, etc.
USE 33.15.F
35.20.Jv Barrier heights (internal rotation, inversion); rotational isomerism, conformational dynamics
USE 33.15.H
35.20.My Electric and magnetic moments (and derivatives), polarizability, and magnetic susceptibility
USE 33.15.K
35.20.Pa Rotation, vibration, and vibration-rotation constants
USE 33.15.M
35.20.Sd Hyperfine- and fine-structure constants
USE 33.15.P
35.20.Vf Ionization potentials, electron affinities, molecular core binding energy
USE 33.15.R
35.20.Wg Mass spectra
USE 33.15.T
35.20.Yh Correlation times in molecular dynamics
USE 33.15.V
35.80.+s Atomic and molecular measurement and techniques
USE 39.10.+ or 39.20.+ or 39.30.+
36.40.+d Atomic and molecular clusters
USE 36.40.-
42.50.Si Self-induced transparency
USE 42.50.M
42.50.Wm Optical tests of fundamental laws and forces
USE 12.20.F and 03.65.B
52.55.Mg Nonmagnetic confinement systems (e.g., electrostatic and high-frequency confinement)
USE 52.58.-
52.65.+z Plasma simulation (e.g., particle orbit and trajectory, MHD equilibrium and stability, initial value computation, and heat transport models; Monte Carlo methods)
USE 52.65.-

NeW PACS Categories Introduced in 1995 Edition

01.50.Wg Physics of toys
01.52.+r National and international laboratory facilities
01.80.+b Physics of sports
06.60.Mr Testing and inspecting procedures
06.60.Yb Other laboratory procedures
07.05.-t Computers in experimental physics
07.05.Bx Computer systems: hardware, operating systems, computer languages, and utilities
07.05.Dz Control systems
07.05.Fb Design of experiments
07.05.Hd Data acquisition: hardware and software
07.05.Kf Data analysis: algorithms and implementation; data management
07.05.Mh Neural networks, fuzzy logic, artificial intelligence
07.05.Pj Image processing
(see also 42.30.V in optics)
07.05.Rm Data presentation and visualization: algorithms and implementation
07.05.Tp Computer modeling and simulation
07.05.Wr Computer interfaces
07.05.Ys Other topics in computers in experimental physics
07.07.-a General equipment and techniques
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
07.07.Hj Display and recording equipment, oscilloscopes, TV cameras, etc.
07.07.Mp Transducers
07.07.Tw Servo and control equipment; robots
07.07.Vx Hygrometers
07.07.Yz Other equipment and techniques
07.10.-h Mechanical instruments, equipment, and techniques
07.10.Cm Micromechanical devices and systems
(see also 85.42 Nanotechnology)
07.10.Fq Vibration isolation
07.10.Lw Balance systems, tensile machines, etc.
07.10.Pz Instruments for strain, force, and torque
07.10.Yg Other mechanical instruments, equipment, and techniques (including pendulum, gyroscopes, centrifuges, etc.)
07.20.Pe Heat engines; heat pumps
07.20.Ym Other thermal instruments and techniques
07.50.-e Electrical and electronic components, instruments, and techniques
07.50.Ek Circuits and circuit components
(see also 85.20--in electrical and magnetic devices)
07.50.Hp Electrical noise and shielding, interference
07.50.Ls Electrometers
07.50.Qx Signal processing electronics
07.50.Yd Other electrical and electronic components, instruments, and techniques
07.55.-w Magnetic components, instruments and techniques
07.55.Db Generation of magnetic fields; magnets
(see also 85.70.N--in magnetic devices)
07.55.Ge Magnetometers for magnetic field measurements
07.55.Jg Magnetometers for susceptibility, magnetic moment, and magnetization measurements
07.55.Nk Magnetic shielding in instruments
07.55.Yv Other magnetic instruments and techniques
07.57.-c Infrared, submillimeter wave, microwave and radiowave instruments, equipment and techniques (for infrared and radio telescopes, see 95.55)
07.57.Hm Infrared, submillimeter wave, microwave, and radiowave sources
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
(see also 85.60.G Photodetectors and infrared detectors)
07.57.Pt Submillimeter wave, microwave and radiowave spectrometers; magnetic resonance spectrometers, auxiliary equipment, and techniques
07.57.Ty Infrared spectrometers, auxiliary equipment, and techniques
07.57.Yb Other infrared, submillimeter wave, microwave, and radiowave instruments, equipment, and techniques
07.60.Rd Visible and ultraviolet spectrometers
07.60.Vg Fiber-optic instruments
(see also 42.81 Fiber optics)
07.60.Yi Other optical instruments, equipment and techniques
07.64.+z Acoustic instruments, equipment, and techniques
07.77.-n Atomic, molecular, and charged-particle sources and detectors
07.77.Gx Atomic and molecular beam sources and detectors
07.77.Ka Charged-particle beam sources and detectors
07.78.+s Electron, positron, and ion microscopes, electron diffractometers, and related techniques
07.79.-v Scanning probe microscopes, components, and techniques
07.79.Cz Scanning tunneling microscopes
07.79.Fc Near-field scanning optical microscopes
07.79.Lh Atomic force microscopes
07.79.Pk Magnetic force microscopes
07.79.Sp Friction force microscopes
07.81.+a Electron, ion spectrometers, and related techniques
07.85.-m X- and gamma-ray instruments and techniques (for x- and gamma-ray telescopes, see 95.55.K)
07.85.Fv X- and gamma-ray sources, mirrors, gratings, and detectors
07.85.Jy Diffractometers
07.85.Nc X-ray and gamma-ray spectrometers
07.85.Qe Synchrotron radiation instrumentation
07.85.Yk Other x-ray and gamma-ray instruments and techniques
07.87.+v Spaceborne and space research instruments, apparatus, and components (satellites, space vehicles, etc.)
07.88.+y Instruments for environmental pollution measurements
07.89.+b Environmental effects on instruments (e.g., radiation and pollution effects)
23.50.+z Decay by proton emission
31.15.-p Calculations and mathematical techniques in atomic and molecular physics (excluding electron correlation calculations)
(for computational techniques, see 02.70)
31.15.Ar Ab initio calculations
31.15.Bs Statistical model calculations (including Thomas-Fermi and Thomas-Fermi-Dirac models)
31.15.Ct Semi-empirical and empirical calculations (differential overlap, Hueckel, PPP methods, etc.)
31.15.Dv Coupled cluster theory
31.15.Ew Density-functional theory
31.15.Fx Finite-difference schemes
31.15.Gy Semiclassical methods
31.15.Hz Group theory
31.15.Ja Hyperspherical methods
31.15.Kb Path-integral methods
31.15.Lc Quasiparticle methods
31.15.Md Perturbation theory
31.15.Ne Self-consistent-field methods
31.15.Pf Variational techniques
31.15.Qg Molecular dynamics and other numerical methods
31.15.Rh Valence bond calculations
31.25.-v Electron correlation calculations for atoms and molecules
31.25.Eb Electron-correlation calculations for atoms and ions: ground state
31.25.Jf Electron-correlation calculations for atoms and ions: excited states
31.25.Nj Electron-correlation calculations for diatomic molecules
31.25.Qm Electron-correlation calculations for polyatomic molecules
32.10.-f Properties of atoms and atomic ions
32.10.Bi Atomic masses, mass spectra, abundances, and isotopes (for mass spectroscopy, see 07.75)
32.10.Dk Electric and magnetic moments, polarizability
32.10.Fn Fine and hyperfine structure
32.10.Hq Ionization potentials, electron affinities
32.80.Gc Photodetachment of atomic negative ions
32.80.Lg Mechanical effects of light on atoms, molecules, and ions
32.80.Qk Coherent control of atomic interactions with photons
32.80.Ys Weak-interaction effects in atoms
33.15.-e Properties of molecules and molecular ions
33.15.Bh General molecular conformation and symmetry; stereochemistry
33.15.Dj Interatomic distances and angles
33.15.Fm Bond strengths, dissociation energies
33.15.Hp Barrier heights (internal rotation, inversion, rotational isomerism, conformational dynamics)
33.15.Kr Electric and magnetic moments (and derivatives), polarizability, and magnetic susceptibility
33.15.Mt Rotation, vibration, and vibration-rotation constants
33.15.Pw Fine and hyperfine structure
33.15.Ry Ionization potentials, electron affinities, molecular core binding energy
33.15.Ta Mass spectra
33.15.Vb Correlation times in molecular dynamics
33.20.Sn Rotational analysis
33.20.Tp Vibrational analysis
33.20.Vq Vibration-rotation analysis
33.20.Wr Vibronic, rovibronic, and rotation-electron-spin interactions
33.25.+k Nuclear resonance and relaxation
33.35.+r Electron resonance and relaxation
33.40.+f Multiple resonances (including double and higher-order resonance processes, such as double nuclear magnetic resonance, electron double resonance, and microwave optical double resonance)
34.50.Dy Interactions of atoms, molecules, and their ions with surfaces; photon and electron emission; neutralization of ions
34.80.Ht Dissociation and dissociative attachment by electron impact
34.80.Lx Electron-ion recombination and electron attachment
34.80.My Fundamental electron inelastic processes in weakly ionized gases
34.80.Pa Coherence and correlation in electron scattering
36.20.Ng Vibrational and rotational structure, infrared and Raman spectra
36.40.-c Atomic and molecular clusters
(see also 61.46 Solid clusters and nanoparticles)
36.40.Cg Electronic and magnetic properties of clusters
36.40.Ei Phase transitions in clusters
36.40.Gk Plasma and collective effects in clusters
36.40.Jn Reactivity of clusters
36.40.Mr Spectroscopy and geometrical structure of clusters
36.40.Qv Stability and fragmentation of clusters
36.40.Sx Diffusion and dynamics of clusters
36.40.Vz Optical properties of clusters
36.40.Wa Charged clusters
39. Instrumentation and techniques for atomic and molecular physics
39.10.+j Atomic and molecular beam sources and techniques
39.20.+q Atom interferometry techniques
(see also 03.75.Dg Atom and neutron interferometry)
39.30.+w Spectroscopic techniques
39.90.+d Other instrumentation and techniques for atomic and molecular physics
41.75.Lx Advanced accelerator concepts
42.55.Ah General laser theory
51.35.+a Mechanical properties; compressibility
52.25.Ya Neutrals in plasma
52.58.-c Nonmagnetic confinement
52.58.Ei Light-ion inertial confinement
52.58.Hm Heavy-ion inertial confinement
52.58.Ns Other inertial confinement (including laser)
52.58.Qv Electrostatic, high frequency, and other nonmagnetic confinement
52.65.-y Plasma simulation
52.65.Cc Particle orbit and trajectory
52.65.Ff Fokker-Planck equation
52.65.Kj Magnetohydrodynamic and fluid equation
52.65.Pp Monte Carlo methods
52.65.Rr Particle-in-cell method
52.65.Tt Gyrofluid and gyrokinetic simulations
52.75.Rx Plasma applications in manufacturing and materials processing (etching, surface cleaning, spraying, arc welding, ion implantation, film deposition, etc.)
52.75.Va Devices for generation of coherent radiation

Modified PACS Categories in 1995 Edition

06. Metrology, measurements, and laboratory procedures
06.20.Fn Units and standards
06.30.-k Measurements common to several branches of physics and astronomy
06.30.Bp Spatial dimensions (e.g., position, lengths, volume, angles, displacements)
06.30.Dr Mass and density
06.30.Ft Time and frequency
06.30.Gv Velocity, acceleration, and rotation
06.60.-c Laboratory procedures
06.60.Ei Sample preparation (including design of sample holders)
06.60.Sx Positioning and alignment; manipulating, remote handling
06.60.Vz Workshop procedures (welding, machining, lubrication, bearings, etc.)
06.60.Wa Laboratory safety procedures
06.90.+v Other topics in metrology, measurements, and laboratory procedures
07. Instruments, apparatus, components, and techniques common to several branches of physics and astronomy
(see also each subdiscipline for specialized instrumentation and techniques)
07.20.-n Thermal instruments, apparatus, and techniques
07.20.Hy Furnaces; heaters
07.20.Mc Cryogenics, refrigerators; low-temperature techniques
07.30.-t Vacuum apparatus and techniques
(see also 47.45 Rarefied gas dynamics)
07.30.Bx Degasification, residual gas
07.30.Dz Vacuum gauges
07.30.Hd Vacuum testing methods; leak detectors
07.30.Kf Vacuum chambers, auxiliary apparatus, and materials
07.35.+k High-pressure apparatus and techniques; shock tubes; diamond anvil cells
07.60.-j Optical instruments, equipment, and techniques
07.60.Dq Photometers, radiometers, and colorimeters
07.60.Fs Polarimeters and ellipsometers
07.60.Hv Refractometers and reflectometers
07.60.Ly Interferometers
07.60.Pb Conventional optical microscopes (for near-field scanning optical microscopes, see 07.79.B)
07.68.+m Photography, photographic instruments and techniques; xerography
07.75.+h Mass spectrometers and related techniques
07.90.+c Other topics in instruments, apparatus, components, and techniques common to several branches of physics and astronomy
23.40.Bw Weak-interaction and lepton (including neutrino) aspects
25.30.Mr Muon scattering (including the EMC effect)
25.70.-z Low and intermediate energy heavy-ion reactions
25.75.+r Relativistic heavy-ion reactions (collisions induced by light ions studied to calibrate relativistic heavy ion collisions, should be classified under both 25.75 and the 13 or 25 category appropriate to the light ions)
29.25.Rm Sources of radioactive nuclei
31. Electronic structure of atoms, molecules and their ions: theory
31.10.+z Theory of electronic structure, electronic transitions, and chemical binding
31.30.Jv Relativistic and quantum electrodynamic effects in atoms and molecules
31.70.-f Effects of atomic and molecular interactions on electronic structure
(see also 34 Atomic and molecular collision processes and interactions)
31.90.+s Other topics in the theory of the electronic structure of atoms, molecules, and their ions
32. Atomic properties and interactions with photons
32.70.Cs Oscillator strengths, lifetimes, transition moments
32.70.Fw Absolute and relative intensities
32.80.Fb Photoionization of atoms and ions
32.80.Hd Auger effect and inner-shell excitation or ionization
32.90.+a Other topics in atomic properties and interactions of atoms and ions with photons
33. Molecular properties and interactions with photons
33.20.-t Molecular spectra
33.50.-j Fluorescence and phosphorescence; radiationless transitions, quenching (intersystem crossing, internal conversion)
(for energy transfer, see also 34)
33.50.Hv Radiationless transitions, quenching
33.70.Ca Oscillator and band strengths, lifetimes, transition moments, and Franck-Condon factors
33.70.Fd Absolute and relative line and band intensities
33.90.+h Other topics in molecular properties and interactions with photons
34.10.+x General theories and models of atomic and molecular collisions and interactions (including statistical theories, transition state, stochastic and trajectory models, etc.)
34.50.-s Scattering of atoms, molecules, and ions
34.80.Gs Molecular excitation and ionization by electron impact
34.80.Kw Electron-ion scattering; excitation and ionization
36. Studies of special atoms, molecules, and their ions; clusters
36.90.+f Other special atoms, molecules, ions, and clusters
42.50.Dv Nonclassical field states; squeezed, antibunched, and sub-Poissonian states; operational definitions of the phase of the field; phase measurements
42.50.Md Optical transient phenomena: quantum beats, photon echo, free-induction decay, dephasings and revivals, optical nutation, and self-induced transparency
50. PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES
(for flow properties of gases, see 47; for atomic and molecular properties, see 30)
51. Physics of gases
51.10.+y Kinetic and transport theory of gases
51.20.+d Viscosity, diffusion, and thermal conductivity
51.30.+i Thermodynamic properties, equations of state
51.40.+p Acoustical properties
(see also 43.28 Aeroacoustics, atmospheric sound)
51.50.+v Electrical properties (ionization, breakdown, electron and ion mobility, etc.)
(see also 52.80 Electric discharges)
51.60.+a Magnetic properties
51.70.+f Optical and dielectric properties
51.90.+r Other topics in the physics of gases
52. Physics of plasmas and electric discharges
(for astrophysical plasmas, see 95.30.Q; for physics of the ionosphere and magnetosphere, see 94.20 and 94.30)
52.35.Py Plasma macroinstabilities (hydromagnetic, e.g., kink, fire-hose, mirror, ballooning, tearing, trapped-particle, flute, Rayleigh-Taylor, etc.)
52.40.Db Electromagnetic (nonlaser) radiation interactions with plasma
52.40.Fd Plasma interactions with antennas; plasma-filled waveguides
52.40.Hf Plasma-wall interactions; boundary layer effects; plasma sheaths
52.40.Mj Particle beam interactions in plasma
52.50.Gj Plasma heating (beam injection, radio-frequency and microwave, ohmic, ICR, ECR, and current drive heating)
52.55.-s Magnetic confinement and equilibrium
52.55.Dy General theory and basic studies of plasma lifetime, particle and heat loss, energy balance, etc.
52.55.Ez Z-Pinch, theta pinch, and other pinch devices
52.55.Hc Stellarators, spheromaks, compact tori, bumpy tori, and other toroidal confinement devices
52.55.Jd Magnetic mirrors
52.55.Lf Astron, cusp, and other magnetic traps
52.55.Pi Fusion products effects (e.g., alpha-particles, etc.)
52.90.+z Other topics in physics of plasmas and electric discharges
95.55.Ka X- and gamma-ray telescopes and instrumentation
98. Stellar systems; interstellar medium; galactic and extragalactic objects and systems; the Universe
98.90.+s Other topics on stellar systems; interstellar medium; galactic and extragalactic objects and systems; the Universe

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