nuclear-reaction models and methods   24.10.-i  
nuclear-structure models and methods   21.60.-n  
nucleation   64.60.Qb  
nucleation # thermodynamics of    82.60.Nh  
nucleation and growth: microscopic aspects   68.55.Ac  
nuclei # reactions induced by unstable    25.60.-t  
nuclei # sources of radioactive    29.25.Rm  
nuclei (including black holes), circumnuclear matter, and bulges # galactic    98.62.Js  
nuclei and nuclear processes # quantum chromodynamics see also 24.85.+p quarks, gluons, and QCD in    12.38.-t  
nuclei and nuclear processes # quarks, gluons, and QCD in    24.85.+p  
nuclei listed by mass ranges (an additional heading must be chosen with these entries, where the given mass number limits are, to some degree, arbitrary) # properties of specific    27.  
nuclei of planetary nebulae # faint blue stars (including blue stragglers), white dwarfs, degenerate stars,    97.20.Rp  
nuclei) # active and peculiar galaxies and related systems (including BL Lacertae objects, blazars, Seyfert galaxies, Markarian galaxies, and active galactic    98.54.Cm  
nuclei; nuclear energy levels # properties of    21.10.-k  
nucleic acids, DNA and RNA bases   82.39.Pj  
nucleon-induced reactions   25.40.-h  
nucleon-nucleon interactions (including antinucleons, deuterons, etc.)   13.75.Cs  
nucleosynthesis # Big_Bang    26.35.+c  
nucleosynthesis # cosmic ray    26.40.+r  
nucleosynthesis # hydrostatic stellar    26.20.+f  
nucleosynthesis in novae, supernovae and other explosive environments   26.30.+k  
nucleosynthesis) # origin, formation, and abundances of the elements (see also 26.35.+c Big_Bang    98.80.Ft  
nucleosynthesis, ages # stellar structure, interiors, evolution,    97.10.Cv  
nucleus # compound    25.70.Gh  
number (creeping) flows # low-Reynolds-   47.15.Gf  
number limits are, to some degree, arbitrary) # properties of specific nuclei listed by mass ranges (an additional heading must be chosen with these entries, where the given mass    27.  
number theory # algebraic structures and    02.10.De  
number turbulence # high-Reynolds-   47.27.Jv  
number) # global symmetries (e.g., baryon number, lepton    11.30.Fs  
number, lepton number) # global symmetries (e.g., baryon    11.30.Fs  
numbers of components (e.g., 1/Nc expansions) # expansions for large    11.15.Pg  
numerical approximation and analysis   02.60.-x  
numerical differentiation and integration   02.60.Jh  
numerical linear algebra   02.60.Dc  
numerical methods # molecular dynamics and other    31.15.Qg  
numerical optimization   02.60.Pn  
numerical relativity   04.25.Dm  
numerical simulation # theory of impact phenomena;    79.20.Ap  
numerical simulation # theory, models, and    78.20.Bh  
numerical simulation studies   75.40.Mg  
numerical simulation; solution of equations   02.60.Cb  
numerical simulations # molecular dynamics calculations (Car - Parrinello) and other    71.15.Pd  
numerical simulations of chaotic models   05.45.Pq  
numerical techniques # analytical and    44.05.+e  
nutation, and self-induced transparency # optical transient phenomena: quantum beats, photon echo, free-induction decay, dephasings and revivals, optical    42.50.Md  
O and B) # main-sequence: early-type stars (   97.20.Ec  
OB, T, R) in external galaxies # associations of stars (   98.20.Bg  
OB, T, R) in the Milky_Way # associations of stars (   98.20.Af  
obeying scaling laws # systems    89.75.Da  
obituaries # biographies, tributes, personal notes, and    01.60.+q  
objects # characteristics and properties of external galaxies and extragalactic    98.62.-g  
objects (YSO's) and protostars (T Tauri stars, Orion population, Herbig-Haro objects, Bok globules, bipolar outflows, cometary nebulae, etc.) # pre-main sequence objects, young stellar    97.21.+a  
objects and systems (by type) # normal galaxies; extragalactic    98.52.-b  
objects and systems; the Universe # other topics on stellar systems; interstellar medium; galactic and extragalactic    98.90.+s  
objects and systems; the Universe # stellar systems; interstellar medium; galactic and extragalactic    98.  
objects and/or properties studied) # astronomical observations (additional primary heading(s) must be chosen with these entries to represent the astronomical    95.85.-e  
objects); symbiotic stars # cataclysmic binaries (novae, dwarf novae, recurrent novae, and nova-like    97.80.Gm  
objects, and systems # quasars; active or peculiar galaxies,    98.54.-h  
objects, blazars, Seyfert galaxies, Markarian galaxies, and active galactic nuclei) # active and peculiar galaxies and related systems (including BL Lacertae    98.54.Cm  
objects, Bok globules, bipolar outflows, cometary nebulae, etc.) # pre-main sequence objects, young stellar objects (YSO's) and protostars (T Tauri stars, Orion population, Herbig-Haro    97.21.+a  
objects, young stellar objects (YSO's) and protostars (T Tauri stars, Orion population, Herbig-Haro objects, Bok globules, bipolar outflows, cometary nebulae, etc.) # pre-main sequence    97.21.+a  
observation and data reduction techniques; computer modeling and simulation   95.75.-z  
observation of dislocations and other defects (etch pits, decoration, electron microscopy, x-ray topography, etc.) # direct    61.72.Ff  
observational cosmology (including Hubble constant, distance scale, cosmological constant, early Universe, etc)   98.80.Es  
observations # fundamental astronomy and astrophysics; instrumentation, techniques, and astronomical    95.  
observations # gravitational radiation, magnetic fields, and other    95.85.Sz  
observations # historical astronomy and archaeoastronomy; and other topics in fundamental astronomy and astrophysics; instrumentation, techniques, and astronomical    95.90.+v  
observations # topography; geometric    91.10.Jf  
observations (additional primary heading(s) must be chosen with these entries to represent the astronomical objects and/or properties studied) # astronomical    95.85.-e  
observations to tectonics and isostasy # relations of gravity    91.45.Sx  
observations, instrumentation, and techniques # geophysical    93.  
observatories and site testing   95.45.+i  
observing techniques # remote    95.75.Rs  
occultations # eclipses, transits, and    95.10.Gi  
occurrences and deposits # mineral    91.65.Rg  
Ocean # Arctic    93.30.Li  
Ocean # Atlantic    93.30.Mj  
Ocean # Indian    93.30.Nk  
Ocean # Pacific    93.30.Pm  
Ocean # Southern    93.30.Qn  
ocean # chemistry of the    92.20.Cm  
ocean # dynamics of the deep    92.10.Dh  
ocean # dynamics of the upper    92.10.Fj  
ocean bottom processes   91.50.Ey  
ocean energy extraction   92.20.Gr  
ocean/Earth/atmosphere interaction   91.10.Vr  
oceanic crust seismology   91.30.Ye  
oceanography # biological aspects of    92.20.Jt  
oceanography # coastal and estuarine    92.10.Sx  
oceanography # interdisciplinary aspects of    92.20.-h  
oceans   92.70.Jw  
oceans # physics of the    92.10.-c  
ODMR) # optically detected magnetic resonance (   76.70.Hb  
Of, Be, Luminous Blue Variables, Wolf - Rayet, etc.) # emission-line stars (   97.30.Eh  
ohmic heating, arcs # plasma heating by DC fields;    52.50.Nr  
one-dimensional conductors) # collective modes (e.g., in    72.15.Nj  
Oort cloud   96.50.Hp  
opacities, rotation constants, line identification, oscillator strengths, gf values, transition probabilities, etc.) # atomic and molecular data, spectra, and spectral parameters (   95.30.Ky  
opacity and line formation # stellar atmospheres (photospheres, chromospheres, coronae, magnetospheres); radiative transfer;    97.10.Ex  
open clusters in external galaxies   98.20.Fk  
open clusters in the Milky_Way   98.20.Di  
open systems; quantum statistical methods # decoherence;    03.65.Yz  
operating systems, computer languages, and utilities # computer systems: hardware,    07.05.Bx  
operation # continuous    42.60.Pk  
operation # laser optical systems: design and    42.60.-v  
operation # relaxation oscillations and long pulse    42.60.Rn  
operational calculus   02.30.Vv  
operational definitions of the phase of the field; phase measurements # nonclassical field states; squeezed, antibunched, and sub-Poissonian states;    42.50.Dv  
operational parameters # efficiency, stability, gain, and other    42.60.Lh  
operator theory   02.30.Tb  
optic-nerve structure and function # physiology of eye;    42.66.Ew  
optical (ultraviolet, visible, infrared) measurements   52.70.Kz  
optical absorption spectra # intrinsic properties of excitons;    71.35.Cc  
optical absorption, magnetic circular dichroism, and fluorescence spectroscopy   87.64.Ni  
optical activity   78.20.Ek  
optical activity and dichroism; magnetooptical and electrooptical spectra   33.55.-b  
optical activity, optical rotation; circular dichroism   33.55.Ad  
optical and dielectric properties   51.70.+f  
optical and dielectric properties (related to treatment conditions)   81.40.Tv  
optical and diffraction models   24.10.Ht  
optical and infrared telescopes # ground-based ultraviolet,    95.55.Cs  
optical bistability, multistability, and switching (see also 42.60.Gd Q-switching; 42.79.Ta optical computers, logic elements, interconnects, switches; neural networks)   42.65.Pc  
optical chaos and complexity, and optical spatio-temporal dynamics # dynamics of nonlinear optical systems; optical instabilities,    42.65.Sf  
optical coatings   42.79.Wc  
optical communication systems, multiplexers, and demultiplexers   42.79.Sz  
optical computers, logic elements, interconnects, switches; neural networks   42.79.Ta  
optical computers, logic elements, interconnects, switches; neural networks) # interconnects, including holographic interconnects (see also 42.79.Td    42.82.Ds  
optical computers, logic elements, interconnects, switches; neural networks) # optical bistability, multistability, and switching (see also 42.60.Gd Q-switching; 42.79.Ta    42.65.Pc  
optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)   78.20.Ci  
optical cooling of atoms; trapping   32.80.Pj  
optical cooling of molecules; trapping   33.80.Ps  
optical creation of spin polarized carriers   72.25.Fe  
optical crystals # nonlinear    42.70.Mp  
optical disks # optical storage systems,    42.79.Vb  
optical double resonance) # multiple resonances (including double and higher-order resonance processes, such as double nuclear magnetic resonance, electron double resonance, and microwave    33.40.+f  
optical elements, devices, and systems   42.79.-e  
optical elements, devices, and systems # radiation effects on    42.88.+h  
optical elements; holographic gratings # holographic    42.40.Eq  
optical frequency converters   42.79.Nv  
optical instabilities, optical chaos and complexity, and optical spatio-temporal dynamics # dynamics of nonlinear optical systems;    42.65.Sf  
optical instruments and equipment   07.60.-j  
optical materials   42.70.-a  
optical materials; photorefractive and semiconductor materials # other nonlinear    42.70.Nq  
optical measurements in condensed matter # time-resolved optical spectroscopies and other ultrafast    78.47.+p  
optical methods # nondestructive testing:    81.70.Fy  
optical methods; rheo-optics   83.85.Ei  
optical microscopes # conventional    07.60.Pb  
optical microscopes # near-field scanning    07.79.Fc  
optical microscopy # near-field scanning    87.64.Xx  
optical mixing, and photorefractive effect # phase conjugation,    42.65.Hw  
optical models # Regge theory, duality, absorptive/   12.40.Nn  
optical nutation, and self-induced transparency # optical transient phenomena: quantum beats, photon echo, free-induction decay, dephasings and revivals,    42.50.Md  
optical parametric oscillators and amplifiers   42.65.Yj  
optical processing # imaging and    42.30.-d  
optical processors, correlators, and modulators   42.79.Hp  
optical properties   91.60.Mk  
optical properties # condensed matter: electonic structure, electrical , magnetic, and    70.  
optical properties of bulk materials and thin films   78.20.-e  
optical properties of clusters   36.40.Vz  
optical properties of nanoscale materials and structures   78.67.-n  
optical properties of sea water   92.10.Pt  
optical properties of specific thin films   78.66.-w  
optical properties of surfaces   78.68.+m  
optical properties, condensed matter spectroscopy and other interactions of particles and radiation with condensed matter # other topics in    78.90.+t  
optical properties, condensed-matter spectroscopy and other interactions of radiation and particles with condensed matter   78.  
optical pulse generation and pulse compression # ultrafast processes;    42.65.Re  
optical pumping # level crossing and    32.80.Bx  
optical pumping # level crossing and    33.80.Be  
optical radiation (near ultraviolet, visible, and infrared)   87.50.Hj  
optical rotation; circular dichroism # optical activity,    33.55.Ad  
optical scattering) # Raman and Rayleigh spectra (including    33.20.Fb  
optical solitons; nonlinear guided waves   42.65.Tg  
optical sources and standards   42.72.-g  
optical spatio-temporal dynamics # dynamics of nonlinear optical systems; optical instabilities, optical chaos and complexity, and    42.65.Sf  
optical spectroscopies and other ultrafast optical measurements in condensed matter # time-resolved    78.47.+p  
optical storage media # holographic recording materials;    42.70.Ln  
optical storage systems, optical disks   42.79.Vb  
optical susceptibility, hyperpolarizability   42.65.An  
optical system design   42.15.Eq  
optical systems: design and operation # laser    42.60.-v  
optical systems; optical instabilities, optical chaos and complexity, and optical spatio-temporal dynamics # dynamics of nonlinear    42.65.Sf  
optical testing techniques   42.87.-d  
optical transfer functions # modulation and    42.30.Lr  
optical transient phenomena: quantum beats, photon echo, free-induction decay, dephasings and revivals, optical nutation, and self-induced transparency   42.50.Md  
optical transitions in quantum systems; multi-photon processes; dynamic stark shift # strong-field excitation of    42.50.Hz  
optical trapping   87.80.Cc  
optical waveguides and couplers   42.79.Gn  
optical workshop techniques   42.86.+b  
optical, and infrared telescopes # space-based ultraviolet,    95.55.Fw  
optical, electrical, movement, gas, etc.); remote sensing # sensors (chemical,    07.07.Df  
optical, structural) of molecules in zeolites # measurements and simulation of properties (   82.75.Mj  
optical, x-ray, and gamma-ray detectors (SIS, NIS, transition edge) # superconducting    85.25.Oj  
optically detected magnetic resonance (ODMR)   76.70.Hb  
optics   42.  
optics # adaptive and segmented    95.75.Qr  
optics # atmospheric    42.68.-w  
optics # atom and neutron    03.75.Be  
optics # beam    41.85.-p  
optics # electromagnetism; electron and ion    41.  
optics # fiber    42.81.-i  
optics # Fourier    42.30.Kq  
optics # geometrical    42.15.-i  
optics # integrated    42.82.-m  
optics # nonlinear    42.65.-k  
optics # other topics in    42.90.+m  
optics # other topics in electromagnetism; electron and ion    41.90.+e  
optics # physiological    42.66.-p  
optics # quantum    42.50.-p  
optics # wave    42.25.-p  
optics # x-ray beams and x-ray    41.50.+h  
optics of eye # anatomy and    42.66.Ct  
optics with polymers # nonlinear    82.35.Ej  
optics, acoustics, heat transfer, classical mechanics and fluid mechanics # elecreomagnetism,    40.  
optimization # numerical    02.60.Pn  
optimization methods # variational and    45.10.Db  
optimization, tissue response factors, and doseromechanical- volume analysis # treatment planning,    87.53.Tf  
optimizational methods # variational and    46.15.Cc  
optoelectronic device characterization, design, and modeling   85.60.Bt  
optoelectronic devices   85.60.-q  
optogalvanic spectroscopic methods) # energy-conversion spectro-analytical methods (e.g., photoacoustic, photothermal, and    82.80.Kq  
oral, electronic, etc.) # communication forms and techniques (written,    01.20.+x  
orbit and trajectory # particle    52.65.Cc  
orbit determination and improvement   95.10.Eg  
orbits # mass, size; gravitational fields; rotation;    96.35.Fs  
orbits # particle    52.20.Dq  
orbits # satellite    91.10.Sp  
order # critical-point effects, specific heats, short-range    75.40.-s  
order # orientational order of liquid crystals; electric and magnetic field effects on    61.30.Gd  
order of liquid crystals; electric and magnetic field effects on order # orientational    61.30.Gd  
order parameter, static susceptibility, heat capacities, critical exponents, etc.) # static properties (   75.40.Cx  
order-disorder # constant-composition solid-solid phase transformations: polymorphic, massive, and    81.30.Hd  
order-disorder transformations; statistical mechanics of model systems   64.60.Cn  
ordered materials # intrinsic properties of magnetically    75.30.-m  
ordered materials (including neutron and spin-polarized electron studies, synchrotron-source x-ray scattering, etc.) # spin arrangements in magnetically    75.25.+z  
ordering # general theory and models of magnetic    75.10.-b  
ordering, wetting, prewetting transitions, and wetting transitions # surface phenomena: alignment, anchoring, anchoring transitions, surface-induced layering, surface-induced    61.30.Hn  
ordinary and partial differential equations; boundary value problems   02.60.Lj  
ordinary differential equations   02.30.Hq  
ordinary neutrinos (electron neutrinos, muon neutrinos, tau neutrinos)   14.60.Lm  
organelles   87.16.Tb  
organic compounds   61.66.Hq  
organic compounds # polymers and    71.20.Rv  
organic compounds # polymers,    61.82.Pv  
organic compounds # polymers;    77.84.Jd  
organic compounds # polymers;    78.66.Qn  
organic compounds # polymers;    79.60.Fr  
organic compounds (including organic semiconductors) # polymers;    72.80.Le  
organic compounds and polymers   78.40.Me  
organic compounds, polymers   78.30.Jw  
organic geochemistry   91.65.Hy  
organic materials # polymers and plastics; rubber; synthetic and natural fibers; organometallic and    81.05.Lg  
organic materials # solid    78.55.Kz  
organic semiconductors) # polymers; organic compounds (including    72.80.Le  
organic-inorganic hybrid nanostructures   81.07.Pr  
organics # polymers and    42.70.Jk  
organisms # effects of radiation and external fields on biomolecules, cells and higher    87.50.-a  
organisms # properties of higher    87.19.-j  
organization in complex systems # structures and    89.75.Fb  
organization, and evaluation # laboratory course design,    01.50.Qb  
organizational activities # announcements, news, and    01.10.-m  
organizational activities # physics    01.10.Hx  
organizations, national and international programs # international    93.55.+z  
organizations; anthropology # social    89.65.Ef  
organometallic and organic materials # polymers and plastics; rubber; synthetic and natural fibers;    81.05.Lg  
organs # mechanical properties of tissues and    87.19.Rr  
orientation # theory and models of crystal growth; physics of crystal growth, crystal morphology and    81.10.Aj  
orientation and texture # structure and morphology; thickness; crystalline    68.55.Jk  
orientation devices # nuclear    29.30.Lw  
orientational order of liquid crystals; electric and magnetic field effects on order   61.30.Gd  
origin and formation of the Universe   98.80.Bp  
origin, acceleration, and interactions) # cosmic rays (including sources,    98.70.Sa  
origin, formation, and abundances of the elements (see also 26.35.+c Big_Bang nucleosynthesis)   98.80.Ft  
origin, formation, and age   96.20.Br  
origin, formation, evolution, age, and star formation   98.35.Ac  
origin, formation, evolution, age, and star formation   98.62.Ai  
origin, formation, evolution, and ages   96.35.Cp  
origins and models of the magnetic field; dynamo theories   91.25.Cw  
Orion population, Herbig-Haro objects, Bok globules, bipolar outflows, cometary nebulae, etc.) # pre-main sequence objects, young stellar objects (YSO's) and protostars (T Tauri stars,    97.21.+a  
Orionis, R Coronae Borealis variables, etc.) # flare stars (UV Ceti, RS Canum Venaticorum, FU    97.30.Nr  
oscillation devices (including Hall effect devices, space-charge-limited devices, and Gunn effect devices) # bulk semiconductor and conductivity    85.30.Fg  
oscillations # relativistic stars: structure, stability, and    04.40.Dg  
oscillations (e.g., ion-acoustic waves) # electrostatic waves and    52.35.Fp  
oscillations (periods less than 12 hours) # free    91.30.Ks  
oscillations and long pulse operation # relaxation    42.60.Rn  
oscillations and waves; helioseismology   96.60.Ly  
oscillations, and instabilities in plasmas and intense beams # waves,    52.35.-g  
oscillations, and stellar seismology # pulsations,    97.10.Sj  
oscillations, chaos, and bifurcations   82.40.Bj  
oscillations, chaos, and bifurcations in physical chemistry and chemical physics) # nonequilibrium and irreversible thermodynamics (see also 82.40.Bj    05.70.Ln  
oscillator and band strengths, lifetimes, transition moments, and Franck - Condon factors   33.70.Ca  
oscillator strengths, gf values, transition probabilities, etc.) # atomic and molecular data, spectra, and spectral parameters (opacities, rotation constants, line identification,    95.30.Ky  
oscillator strengths, lifetimes, transition moments   32.70.Cs  
oscillators # synchronization; coupled    05.45.Xt