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Author name code: cooper
ADS astronomy entries on 2022-09-14
=author:"Cooper, J." year:1965-1995

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Title: The Space Physics Data System - Cosmic and Heliospheric Nodes
Authors: Garrard, T. L.; Cooper, J.; Cummings, A.; Gazis, P.; Guzik,
   T. G.; Kurth, W.; Lazarus, A.; McNutt, R.; Pyle, R.; Smith, C. W.
1995icrc...24...84G    Altcode:
  No abstract at ADS

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Title: Collisional Interference in the Rotational Spectrum of HD-He
Authors: Tabisz, G. C.; McQuarrie, B.; Gao, B.; Cooper, J.
1995ASPC...81..312T    Altcode: 1995lahr.conf..312T
  No abstract at ADS

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Title: Rotational spectrum of HD perturbed by He or Ar gases: The
    effects of rotationally inelastic collisions on the interference
    between allowed and collisionally induced components
Authors: Gao, Bo; Cooper, J.; Tabisz, G. C.
1992PhRvA..46.5781G    Altcode:
  The spectral line shapes for the HD rotational spectra perturbed by He
  and Ar gases, which show interference between allowed and collisionally
  induced dipole transitions, are calculated including the effects of
  inelastic rotational collisions. The general parametrization of the
  line shape, including inelastic collisions, requires six independent
  real parameters as opposed to four in the theory of Herman, Tipping,
  and Poll [Phys. Rev. A 20, 2006 (1979)]. Semiclassical calculations
  based on classical trajectories indicate the importance of the
  inelastic effects and show qualitative agreement with the experimental
  parameters. However, it is clear that a full explanation of experimental
  data will eventually require a full quantum treatment.

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Title: Spectral line shape arising from collisional interference
    between electric-dipole-allowed and collision-induced transitions
Authors: Gao, B.; Tabisz, G. C.; Trippenbach, M.; Cooper, J.
1991PhRvA..44.7379G    Altcode:
  A theory is developed to describe the spectral line shape due to
  interference between electric-dipole-allowed and collision-induced
  transitions in pure rotational molecular spectra. Motivation was
  provided by experimental data available for HD-inert gas systems. This
  theory is based on a master-equation approach to induced spectra
  employed by Alber and Cooper [Phys. Rev. A 33, 3084 (1986)]. The active
  molecule is considered to be immersed in a bath of perturbers. An
  expression for the absorption coefficient is obtained within the binary
  collision approximation that contains terms due to allowed, induced,
  and interference contributions. Effects due to m mixing, J mixing,
  and successive collisions are included. Low-order approximations of
  the theory eventually reduce to results of earlier efforts, namely, the
  pioneering description of collisional interference by Herman, Tipping,
  and Poll [Phys. Rev A 20, 2006 (1979)] and refinements to it through
  consideration of rotational level mixing. The principal attribute
  of this approach is the treatment of allowed and collision-induced
  transitions in a consistent manner.

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Title: Estimation of ion velocity and temperature from asymmetric
    model incoherent scatter spectra
Authors: Cooper, J.; Kohl, H.
1990JATP...52..483C    Altcode:
  A simple relaxation collision model is used to obtain line-of-sight ion
  velocity distributions and incoherent scatter spectra for ion-neutral
  collision frequency of comparable order to the ion gyro-frequency and
  crossed electric and magnetic fields. The deduced Doppler shift and
  Maxwellian temperature estimates are compared with the line-of-sight
  ion mean velocities and plasma temperatures in the model. The spectrum
  parameter estimates arise from the fitting of a Maxwellian spectrum to
  the relaxation model spectrum using standard procedures. The deviation
  of these estimates from the given parameters of the ion velocity
  distribution for different electric field strengths and directions of
  observation are discussed. Spectrum estimates depart most from plasma
  parameters for viewing directions across the electric field.

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Title: An overview of the ion dynamic effect in line broadening,
    and a generalization of the unified theory.
Authors: Kelleher, D. E.; Oza, D. H.; Cooper, J.; Greene, R. L.
1990JQSRT..44..101K    Altcode:
  The authors present a brief overview of the collisional broadening
  of hydrogenic radiators in thermal plasmas. Their focus is on
  lines with unshifted central components, particularly the alpha
  lines (Δn = 1), for which ion motion effects can be very large. The
  calculations span a wide range of electron densities, temperatures, and
  radiator-ion perturber reduced masses μ. The computations were made
  using a numerical simulation approach. Numerical methods have proven
  nesessary to deal with the overlapping strong collisions of different
  ion perturbers. Most current analytical methods, such as the unified
  theory, are not valid when strong collisions overlap, as is often the
  case with ion perturbers. The authors are developing a generalization
  of the unified theory which endeavors to overcome this limitation.

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Title: Asymmetric incoherent scatter spectra from a relaxation
    collision model
Authors: Cooper, J.; Kohl, H.
1990JATP...52..133C    Altcode:
  A relaxation collision model for ion flow through a stationary
  neutral gas has been used to obtain ion velocity distributions and
  line-of-sight incoherent scatter spectra for a range of values of
  collision frequency and electric field. The mean velocity of the
  line-of-sight ion velocity distribution has been compared with the
  Doppler shift of the corresponding spectra. The latter is not always
  a good estimate of the former, because the ion velocity distribution
  in the plane perpendicular to the magnetic field direction is highly
  distorted. For ion-neutral collision frequency to ion gyrofrequency
  ratios (IGRs) 0.1-0.5, the greatest inaccuracies in mean velocity
  estimation take place along the electric field direction, while for
  IGRs = 0.5-1.0 the greatest inaccuracies occur across the electric field
  direction. These inaccuracies would be reduced but not eliminated in a
  more realistic model. At F-region altitudes, other processes must be
  invoked to explain observed asymmetrical spectra, but the comparison
  of mean line-of-sight ion velocity and spectrum Doppler shift may
  still have relevance.

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Title: Approximate Formulation of Redistribution in the LY alpha ,
    LY beta , H alpha System
Authors: Cooper, J.; Ballagh, R. J.; Hubeny, I.
1989ApJ...344..949C    Altcode:
  Simple approximate formulas are given for the coupled redistribution of
  Ly-alpha, Ly-beta, and H-alpha, by using well-defined approximations to
  an essentially exact formulation. These formulas incorporate all the
  essential physics including Raman scattering, lower state radiative
  decay, and correlated terms representing emission during a collision
  which must be retained in order that the emission coefficients are
  properly behaved in the line wings. Approximate expressions for
  the appropriate line broadening parameters are collected. Finally,
  practical expressions for the source functions are given. These are
  formulated through newly introduced nonimpact redistribution functions,
  which are shown to be reasonably approximated by existing (ordinary
  and generalized) redistribution functions.

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Title: Redistribution in astrophysically important hydrogen lines
Authors: Cooper, J.; Ballagh, R. J.; Hubeny, I.
1989STIN...8924251C    Altcode:
  Under typical solar chromospheric conditions for hydrogen radiators,
  strong collisions due to both electrons and ions are well separated in
  time, so that a binary collision theory for collisional redistribution
  is applicable. However, a simple impact approximation may not be
  used, but rather a unified type theory is required in which frequency
  dependent line shape parameters are used to describe both impact and
  quasi-static regions of the spectrum. In addition, correlated terms
  which describe absorption and emission during a collision are important,
  and, in fact, without correlated terms describing both transfer of
  excitation and emission during the same collision unphysical predictions
  (such as negative intensities) would be obtained. In this paper theory
  is specifically developed for the coupled Lyman-alpha, Lyman-beta,
  Hydrogen-alpha system, and equations of statistical equilibrium and
  absorption and emission coefficients are given. All correlated events
  are examined and emission during a collision is found to be important
  in the line wings. Stimulated emission and absorption is also included
  within a broadband approximation. The major approximation is to ignore
  lower state interaction. It is found that for Lyman-beta Raman-coupling
  with Hydrogen-alpha occurs and the overall scattering of radiation in
  the line wings is mostly coherent. In contrast, for Hydrogen-alpha,
  incoherent redistribution due to lower state radiative decay (which
  occurs even in the absence of collisions) is found to dominate
  the coherent scattering. Finally, in the Lyman series the dominant
  incoherent contribution is associated with cascade transitions and
  inelastic collisions between different principal quantum states.

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Title: Transfer and Redistribution of Polarized Light in Resonance
    Lines. I. Quantum Formulation with Collisions
Authors: Streater, A.; Cooper, J.; Rees, D. E.
1988ApJ...335..503S    Altcode:
  Equations are derived quantum mechanically for the radiative transfer
  of polarized light and statistical equilibrium governing the formation
  of resonance lines in nonhydrogenic species. Redistribution due
  to collisions is specifically included, but magnetic fields are
  neglected. The formulation accounts for excited level interference
  and optical pumping and is applicable to solar resonance lines such
  as Ca II H and K and Mg II h and k.

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Title: Experiments on time-dependent radiative transfer in a
    spectral line.
Authors: Streater, A.; Molander, W.; Cooper, J.
1988JQSRT..40..101S    Altcode:
  The spatial and temporal evolution of excited atoms in an optically
  thick magnesium vapor after an initial pulsed laser excitation
  is measured using a delayed pulsed probe laser. The collisional
  environment of the magnesium atoms in the vapor is modified by an
  argon buffer gas. Angle-averaged partial and complete redistribution
  calculations are presented and compared with the data. Other aspects
  of the radiative transfer process are discussed.

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Title: Direct probing of the radiation field in optically thick
    environments.
Authors: Streater, A.; Cooper, J.
1988JQSRT..39...49S    Altcode:
  The directional dependence of escaping resonance radiation after an
  initial excitation in an optically thick atomic magnesium vapor is
  measured using a small sapphire rod as a probe. The rod acts as a
  light pipe to bring the radiation directly out from deep within the
  vapor. The time-dependent signal is observed in various directions
  relative to the initial excitation and a significant anisotropy is
  observed, especially at early times. The anisotropy is not strongly
  dependent on the argon buffer gas pressure, and is greater further
  from the initial excitation. The signal is compared with a calculated
  signal under the assumption of complete redistribution.

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Title: Unified description of radiative and dielectronic
    recombination, including the coupling between autoionization and
    radiation continua
Authors: Jacobs, V. L.; Cooper, J.; Haan, S. L.
1987PhRvA..36.1093J    Altcode:
  A unified description of radiative and dielectronic recombination
  is presented that incorporates a nonperturbative treatment of the
  electromagnetic coupling between the autoionization and radiative
  decay continua. Particular attention is given to the angular
  momentum degeneracy of the atomic levels and to the multiplicity of
  angular momentum components in the partial-wave expansion for the
  electron-continuum state. Through the introduction of vertex functions
  and of a modified propagator, the S matrix describing the combined
  electron-ion photorecombination process is expressed as the sum of
  a resonant and a nonresonant transition amplitude. Future extensions
  to incorporate multicontinuum-channel recombination, the effects of
  overlapping autoionizing resonances, renormalization, and the effects
  of collisional dephasing processes and plasma electric microfields
  are discussed.

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Title: Solar Neutron Emissivity during the Large Flare on 1982 June 3
Authors: Chupp, E. L.; Debrunner, H.; Flueckiger, E.; Forrest, D. J.;
   Golliez, F.; Kanbach, G.; Vestrand, W. T.; Cooper, J.; Share, G.
1987ApJ...318..913C    Altcode:
  For the solar neutron event on June 3, 1982, it is shown here that
  the combined SMM Gamma Ray Spectrometer and Jungfraujoch neutron
  monitor data require a time-extended emission of neutrons at the sun
  with energies of 100 MeV to about 2 GeV. The solar neutron emissivity
  spectrum is shown to have a strong downward curvature or truncation
  between 2 and 4 GeV. A Bessel function and truncated power law give
  acceptable fits to the observational data, but only the power law can
  explain the rapid rise of the neutron monitor count rate. The integrated
  emissivity of neutrons above E(n) of 100 MeV is strongly constrained
  at 8 x 10 to the 28th neutrons/sr and is essentially independent
  of neutron spectral shape. At neutron energies of about 100 MeV,
  good agreement is found for both spectral forms with observations of
  neutron decay protons.

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Title: On time-dependent radiative transfer.
Authors: Streater, A.; Cooper, J.; Sandle, W.
1987JQSRT..37..151S    Altcode:
  An integral equation is developed for application to time-dependent
  laboratory experiments in which partial redistribution effects
  are important. The equation of transport with the Heasley-Kneer
  emission coefficient and the equation of statistical equilibrium
  lead to a time-dependent redistribution function containing an
  absorption-re-emission term which decays exponentially in time and a
  scattering term which is instantaneous. This integral equation does
  not agree with an equation written by Payne et al. that has been used
  to compare theory with experiments.

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Title: Observation of radiative transfer of polarized light.
Authors: Belsley, M.; Streater, A.; Burnett, K.; Ewart, P.; Cooper, J.
1986JQSRT..36..163B    Altcode:
  The results of an experiment sensitive to polarization and
  angle-dependent effects of resonance line radiation transport
  in a collisional environment are presented. Having measured both
  the excited atomic state population and alignment as a function of
  distance from the initial excitation, considerable anisotropy in the
  alignment is found. Included in the discussion are the results of an
  angle-average model calculation, which allows the authors to point out,
  in a qualitatively way, some of the important physics of the problem.

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Title: Redistribution of Radiation in the Presence of
    Velocity-changing Collisions
Authors: Hubeny, I.; Cooper, J.
1986ApJ...305..852H    Altcode:
  Starting with the recent work of Cooper et al., a suitable form
  of the normalized redistribution function relevant for a treatment
  of redistribution in the presence of velocity-changing collisions
  is presented. Attention is devoted to provide practical estimates
  of the ratio between the usual line-broadening parameters and the
  velocity-changing rate. It is shown that for virtually all cases of
  astrophysical interest the effect of velocity-changing collisions is
  quite negligible.

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Title: Very energetic gamma-rays from the 3 June 1982 solar flare
Authors: Forrest, D. J.; Vestrand, W. T.; Chupp, E. L.; Rieger, E.;
   Cooper, J.; Share, G. H.
1986AdSpR...6f.115F    Altcode: 1986AdSpR...6..115F
  The Gamma-Ray Spectrometer on the Solar Maximum Mission satellite has
  recorded high energy gamma-ray and neutron emission from the flare on
  3 June 1982. During the 65 sec. impulsive phase the gamma rays >
  10 MeV contains emissions from both primary electron bremsstrahlung
  and nuclear pion decay. Hence the impulsive phase acceleration process
  must produce both primary electrons with energies > 60 MeV and ions
  >500 MeV. This flare also has a extended emission phase lasting more
  than 1000 sec which is most easily observed at gamma-ray energies >
  10 MeV. After removing the counting rates from the more slowly moving
  neutrons produced at earlier times, the resulting gamma ray spectrum can
  be entirely explained by nuclear pion production. We find that >70 %
  of the pions were produced in the extended emission phase. In contrast,
  more than 70 % of the high energy primary electron bremsstrahlung
  and the < 30 MeV ion produced nuclear line emission occured in the
  65 sec impulsive phase. This represents the first clear observation
  of a new acceleration process which produces a electron deficient,
  very hard ion spectrum extending beyond 1000 MeV.

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Title: The classification of distorted-mirror reflections and its
    ionospheric modification due to the underlying ionization
Authors: Cummack, C. H.; Cooper, J.
1986JATP...48...51C    Altcode:
  A systematic classification of reflections from a sinusoidally
  distorted-mirror has led to the identification of three classes of rays;
  direct simple rays which hit the mirror once on reflection; direct
  complex rays which hit the mirror several times before reflection;
  indirect rays which leave from and return to the source at different
  angles. The conditions on the distortion amplitude, wavelength and
  height for the different classes to exist are obtained. A comparison of
  results is made with those from a Chapman layer with a sinusoidally
  varying height of peak density, in the absence of any magnetic
  field. The broad classification of solutions is preserved, but direct
  and indirect rays are no longer independent and at large scale heights
  the presence of underlying ionization removes some solutions. The
  construction of ionograms of these profiles shows that indirect and
  complex direct rays contribute significantly to the traces observed.

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Title: Effect of quasi-bound states on collisional redistribution.
Authors: Belsley, M.; Alford, W. J.; Burnett, K.; Cooper, J.
1986JQSRT..35...53B    Altcode:
  The authors derive an expression for the collisional redistribution of
  radiation due to states trapped by an excited state potential barrier
  in the limit of no subsequent collisions during the excited state
  lifetime. By considering two simple models, the authors suggest three
  possible methods of qualitatively determining excited state well depths
  when no detailed knowledge of the ground or excited state interaction
  potentials exists a priori.

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Title: The analysis of a travelling ionospheric disturbance with
    non-linear ionization response
Authors: Cooper, J.; Cummack, C. H.
1986JATP...48...61C    Altcode:
  Ionograms from a triangular array of ionosondes, are analyzed to yield
  the characteristics of an internal gravity wave throughout the F-region
  overlays, which measure the shape of the ionogram near the F1-cusp, give
  a good estimate of wave amplitude. An internal gravity wave generates
  a non-linear response in the ionospheric electron density profiles,
  which have the characteristics of thick ledges. The ionograms show
  external hooks associated with such ledges.

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Title: Two-photon collisional redistribution of radiation
Authors: Alber, G.; Cooper, J.
1985PhRvA..31.3644A    Altcode:
  Collisional redistribution in the presence of two weakly exciting
  laser fields is studied, including the effects due to degeneracy of
  the radiator states. A general expression for the total redistributed
  intensity is derived valid for arbitrary detunings and polarizations
  of the exciting laser fields. In particular, this expression contains
  all single-collision and sequential-collision contributions, which
  are equally important under certain circumstances. The similarities
  and differences between the redistributed intensity as calculated
  in this paper and the collisionally aided radiative excitation cross
  sections studied by Yeh and Berman (1979) and Light and Szoke (1978)
  are pointed out.

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Title: Redistribution of radiation in the absence of collisions
Authors: Lombardi, G. G.; Kelleher, D. E.; Cooper, J.
1985ApJ...288..820L    Altcode:
  Redistribution and depolarization of near-resonant radiation is
  studied for the He 2(1P)-3(1D) line (668 nm) and some data for
  H-alpha (656 nm) are also presented. A Nd:YAG pumped dye laser, with
  a bandwidth of 0.1/cm and a power density of 100 kW/sq cm, is used in
  the experiment. The transitions have lower levels with natural line
  widths that are large compared with their upper-level natural widths,
  and, under experimental conditions, their collisional widths are also
  small. The ratio of fluorescence to Rayleigh intensity is measured
  and the results indicate that while the Rayleigh emission has the same
  temporal development as the laser pulse (5 ns FWHM), the fluorescent
  intensity has a decay time determined by the radiative decay lifetime
  and by collisional quenching. The prediction that redistribution of
  radiation occurs in the absence of collisions for transitions having
  significant lower-level radiative widths is confirmed. Depolarization
  rates by collisions with helium are also inferred from the measurements.

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Title: Collisional redistribution of light: Far-wing line shapes
    and polarizations for the Ba-(Ar,Xe) systems
Authors: Alford, W. J.; Andersen, N.; Burnett, K.; Cooper, J.
1984PhRvA..30.2366A    Altcode:
  The far-wing collisional redistribution line shape, the redistributed
  fluorescence polarization, and the collisional alignment decay rates
  have been measured for barium perturbed by argon and xenon. The
  experiment was performed with a heated gas cell (T = 900 K) with
  perturber-gas densities in the 1-30-torr range and laser light
  detuned + or - 3-1000/cm from the 5535-A Ba I 6(1)S-6(1)P resonance
  line. Metal-vapor densities were determined by a Rayleigh scattering
  technique which is outlined in detail. By correlating structure
  in the line shape with that of the polarization, it is possible to
  make definitive statements about the interatomic potentials. The Ba
  data show strong similarities with previous experimental results for
  similar two-electron atoms, namely Ca, Sr, and Hg, and so the present
  conclusions are of relevance to these systems as well.

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Title: Properties of Flares Having Emission > 10 MeV
Authors: Forrest, D. J.; Vestrand, W. T.; Rieger, E.; Cooper, J.;
   Chupp, E. L.; Share, G.
1984BAAS...16Q.475F    Altcode:
  No abstract at ADS

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Title: Radiative transfer equations in broad-band, time-varying fields
Authors: Cooper, J.; Zoller, P.
1984ApJ...277..813C    Altcode:
  A derivation of the equation of transfer is obtained by starting with
  Maxwell's equations in the "slowly varying envelope" form. Particular
  attention is paid to characterizing the intensity that is "seen" by
  the atom (which is found to be related to a Wigner distribution of
  the electric field). The equation of transfer is found to be valid for
  "broad-band" slowly varying radiation fields.

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Title: On the line profile coefficient for stimulated emission
Authors: Cooper, J.; Hubeny, I.; Oxenius, J.
1983A&A...127..224C    Altcode:
  It is pointed out that the line profile coefficients for spontaneous and
  stimulated emission are identical in low-intensity radiation fields. In
  more intense radiation fields, however, the stimulated emission profiles
  in the radiative transfer equation and in the rate equations for the
  atomic level populations may differ from each other, owing to their
  different physical nature. A seeming discrepancy between the stimulated
  emission profiles of the usual semi-classical approach and a recent
  quantum mechanical approach by Cooper et al. (1982), which should
  also be valid for intense "broadband" fields, is discussed and shown
  to have negligible consequences for low-intensity radiation fields.

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Title: Polarization of collisionally redistributed light from the
    far wings of strontium-rare-gas systems
Authors: Alford, W. J.; Burnett, K.; Cooper, J.
1983PhRvA..27.1310A    Altcode:
  We have made systematic measurements of the polarization of fluorescence
  from Sr-rare-gas systems excited off resonance by linearly polarized
  light. Measurements of this type give information about the evolution
  during a collision after the absorption of a photon. This information
  is important in obtaining and verifying aspects of the interaction
  potential that cannot be studied using conventional line-broadening
  experiments. We have also measured the collisional-alignment decay
  rates for Sr-rare-gas systems by observing the perturber-pressure
  dependence of the polarization of the fluorescence. To the best of
  our knowledge this is a new technique for measuring these decay rates.

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Title: Theory of time-dependent intense-field collisional resonance
    fluorescence
Authors: Kleiber, P. D.; Cooper, J.; Burnett, K.; Kunasz, C. V.;
   Raymer, M. G.
1983PhRvA..27..291K    Altcode:
  The time-dependent theory of Courtens and Szoke (1977) is generalized
  using the approach of Burnett et al. (1982) to derive time-dependent
  spectral intensities of resonance fluorescence from atoms driven by a
  pulsed laser in the presence of collisions. These results are valid
  both for laser detunings inside and outside the usual impact region
  of the spectrum, including Zeeman degeneracy effects. This theory is
  applied to a simple but important example (J = 0 to J = 1) to obtain
  quantitative predictions for the observable scattered-light spectrum
  which can be directly compared with recent experiments.

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Title: On redistribution and the equations for radiative transfer
Authors: Cooper, J.; Ballagh, R. J.; Burnett, K.; Hummer, D. G.
1982ApJ...260..299C    Altcode:
  The derivation of the equations of statistical equilibrium are
  outlined, starting from the quantum density-matrix equations,
  drawing particular attention to the approximations and assumptions
  used in the development of tractable expressions. Then, using the
  quantum-fluctuation-regression theorem, emission and absorption
  coefficients are obtained for multilevel atomic systems which are
  nondegenerate except for m-substates. These coefficients are valid to
  first order in the incident intensity. Possible extensions to higher
  intensity broadband incoherent fields are suggested.

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Title: Comment on the use of an exponential approximation for the
    Stark broadening of hydrogen lines.
Authors: Cooper, J.; Smith, E. W.
1982JQSRT..27..665C    Altcode:
  No abstract at ADS

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Title: Redistribution of radiation for the wings of Lyman-alpha
Authors: Yelnik, J. -B.; Burnett, K.; Cooper, J.; Ballagh, R. J.;
   Voslamber, D.
1981ApJ...248..705Y    Altcode:
  Earlier work on redistribution of radiation by collisions for isolated
  lines is extended to overlapping lines, and an explicit expression for
  the frequency redistribution is given for Lyman-alpha. This expression
  is valid, even when the emitted photon is in the (non-impact) line
  wings. A simple physical explanation of the result is possible.

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Title: An analysis of Markovian model microfield methods for Stark
    broadening.
Authors: Smith, E. W.; Talin, B.; Cooper, J.
1981JQSRT..26..229S    Altcode:
  No abstract at ADS

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Title: Collisional redistribution of radiation. I. The density matrix
Authors: Burnett, K.; Cooper, J.; Ballagh, R. J.; Smith, E. W.
1980PhRvA..22.2005B    Altcode:
  As a first step in deriving accurate, calculable expressions for
  collisional redistribution of radiation, valid outside the impact
  regime a method for calculating an accurate binary-collision density
  operator for an atom in the presence of a driving field and perturbers
  is presented. Projection-operator techniques to establish first
  the precise validity of the Markoff approximation for radiative
  relaxation are used. Using the same techniques, it is shown how the
  collisional-relaxation problem may be analyzed in a practical manner
  outside the Markoff approximation. The effect of correlations between
  radiative and collisional events is included in a consistent way and
  the physical implications of these correlation effects are demonstrated
  for a simple example, the two-level atom with nondegenerate levels.

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Title: Collisional redistribution of radiation. III. The equation
    of motion for the correlation function and the scattered spectrum
Authors: Burnett, K.; Cooper, J.
1980PhRvA..22.2044B    Altcode:
  Computations were made of the scattering of monochromatic radiation
  by a degenerate atom in the binary-collision approximation for field
  strengths whose products of the Rabi frequency for atomic transition and
  the duration of a strong collision are much less than 1. An expression
  of motion for the correlation function is derived which does not exclude
  the region where thermal correlations may be neglected; the equation is
  valid outside the quantum-regression regime, and has a straightforward
  solution for practical cases. Solutions for the weak-field linear
  response regime are presented in terms of generalized absorption and
  emission profiles which depend on the indices of the atomic multipoles.

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Title: Collisional redistribution of radiation. II. The effects of
    degeneracy on the equations of motion for the density matrix
Authors: Burnett, K.; Cooper, J.
1980PhRvA..22.2027B    Altcode:
  The effect of correlations between an absorber atom and perturbers
  in the binary-collision approximation are applied to degenerate
  atomic systems. A generalized absorption profile which specifies
  the final state of the atom after an absorption event is related to
  the total intensities of Rayleigh scattering and fluorescence from
  the atom. It is suggested that additional dynamical information to
  that obtainable from ordinary absorption experiments is required in
  order to describe redistributed atomic radiation. The scattering
  of monochromatic radiation by a degenerate atom is computed in a
  binary-collision approximation; an equation of motion is derived for
  the correlation function which is valid outside the quantum-regression
  regime. Solutions are given for the weak-field conditions in terms
  of generalized absorption and emission profiles that depend on the
  indices of the atomic multipoles.

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Title: Observation of dynamic correlations in collisional
    redistribution and depolarization of light
Authors: Thomann, P.; Burnett, K.; Cooper, J.
1980PhRvL..45.1325T    Altcode:
  Theory shows that to explain the polarization of light collisionally
  redistributed from the far line wings of an atomic transition, one must
  consider correlated events in which absorption during a collision,
  and propagation to the final Zeeman-state superposition at the end
  of the collision is important. Polarizations of up to about 40% have
  been measured in the far line wings, substantially confirming this
  prediction, and showing that scattering experiments cannot just be
  characterized by simple absorption or emission profiles.

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Title: Zeeman degeneracy effects in collisional intense-field
    resonance fluorescence
Authors: Cooper, J.; Ballagh, R. J.; Burnett, K.
1980PhRvA..22..535C    Altcode:
  Resonance fluorescence due to intense laser fields from
  a Zeeman degenerate atom being perturbed by collisional
  interactions is calculated in the impact regime by using the
  quantum-fluctuation-regression theorem. Various interesting effects are
  found. For example, the scattered intensity spectrum for a J = 0 to
  J = 1 transition for polarization parallel to the laser polarization
  is essentially an asymmetric triplet, whereas for a perpendicular
  polarization due to collisions the spectrum is essentially a doublet
  (whose frequencies do not correspond with any of those of the
  triplet). Further, the width of the fluorescent component (whose
  frequency is close to the unperturbed frequency) actually decreases
  with increasing laser power.

---------------------------------------------------------
Title: Resonance fluorescence in a weak radiation field with arbitrary
    spectral distribution
Authors: Raymer, M. G.; Cooper, J.
1979PhRvA..20.2238R    Altcode:
  The authors show that the laser bandwidth effects in resonance
  fluorescence at low intensities can be treated most readily in terms
  of simple convolutions, and further that this approach allows one to
  consider an incident field with an arbitrary spectral distribution,
  with or without the presence of atomic (line-broadening) collisions.

---------------------------------------------------------
Title: Redistribution Theory of Lyman β Radiation
Authors: Rousseldupre, D. C.; Cooper, J.; Ballagh, R. J.
1979BAAS...11..411R    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Redistribution of scattered radiation by collisions in the
    nonimpact region of the spectral line profile.
Authors: Cooper, J.
1979ApJ...228..339C    Altcode:
  The scattering of radiation in the presence of collisions can
  be described quantum-mechanically in terms of essentially two
  processes. The first may be thought of as an absorption to the excited
  state followed subsequently (after propagating in the excited state)
  by emission. This gives rise to radiation redistributed about the
  transition frequency. The effects of m-degeneracy are particularly
  interesting for this first process. As an example a case is considered
  in which the incident frequency is in the quasi-static line wing, while
  the scattered frequency is close to the line center. It is found that
  under these circumstances the dominant contribution from this process
  in the scattered spectrum is obtained for an absorption of the incident
  frequency taking place during a strong (close) collision and reemission
  of the scattered frequency when the atom is essentially unperturbed

---------------------------------------------------------
Title: Stark broadening of Fe I 5383 Å.
Authors: Freudenstein, S.; Cooper, J.
1979A&A....71..283F    Altcode:
  Results are reported for a laboratory measurement of the electron
  broadening of the Fe I line at 5383 A as a function of electron
  density over the temperature range from 8000 to 12,000 K. A linear
  Z-pinch electrical discharge served as the spectroscopic light source
  in the experiment, and special precautions were taken to allow for
  optical-depth effects, which have been a major source of error in
  previous investigations. The results obtained include a Stark-broadening
  constant of 0.106 + or - 0.004 x 10 to the -16th A-cu cm at a mean
  temperature of 9500 K, an estimated Stark width/electron-broadened
  width ratio of 1.09 + or - 0.02, and a normalized electron-broadened
  width of 0.097 + or - 0.004 x 10 to the 16th A-cu cm. Comparison of the
  last result with a calculated value and with a previous measurement
  indicates that the present measurement is approximately 38% larger
  than the value measured earlier.

---------------------------------------------------------
Title: A simple formula for estimating Stark widths of neutral lines.
Authors: Freudenstein, S. A.; Cooper, J.
1978ApJ...224.1079F    Altcode:
  A simple formula for the prediction of Stark widths of neutral lines
  similar to the semiempirical method of Griem (1968) for ion lines is
  presented. This formula is a simplification of the quantum-mechanical
  classical path impact theory and can be used for complicated atoms for
  which detailed calculations are not readily available, provided that
  the effective position of the closest interacting level is known. The
  expression does not require the use of a computer. The formula has
  been applied to a limited number of neutral lines of interest, and the
  width obtained is compared with the much more complete calculations of
  Bennett and Griem (1971). The agreement generally is well within 50%
  of the published value for the lines investigated. Comparisons with
  other formulas are also made. In addition, a simple estimate for the
  ion-broadening parameter is given.

---------------------------------------------------------
Title: Role of collisional repopulation of atomic levels on coherent
    and redistributed components in resonant light scattering
Authors: Cooper, J.; Ballagh, R. J.
1978PhRvA..18.1302C    Altcode:
  Resonant scattering (redistribution) of weak monochromatic light by
  atoms in the presence of collisions has been considered by Omont et
  al., who allowed for the broadening of both upper and lower levels
  of the transition. Mollow (who also has considered this problem for
  intense radiation) has shown that their results are applicable only
  if collisional repopulation of the levels (in contrast to collisional
  depopulation) is ignored. We here consider in detail the effect of
  repopulation. It leads, in the weak-field limit, to a true-coherent
  component (δ-function spectrum) at the driving frequency, as well as a
  component at this frequency whose width is essentially the inelastic
  collisional rate of the lower state. An additional redistributed
  component due to repopulation of the upper level is also obtained.

---------------------------------------------------------
Title: The angular dependence of partially redistributed resonance
    radiation.
Authors: Ballagh, R. J.; Cooper, J.
1977ApJ...213..479B    Altcode:
  Explicit expressions for the angular distribution and frequency
  dependence of radiation scattered by a spatially degenerate atom
  undergoing collisions are derived using a previously developed
  formalism of the quantum theory of line broadening for an atom
  in its rest frame. Results valid in the impact regime for resonant
  scattering are presented for the cases of linear incident and scattered
  polarization circular incident and linear scattered polarization,
  and unpolarized incident radiation with no monitoring of the scattered
  polarization. These results relate to scattering involving a j - j +
  or - 1 - j atomic transition, with lower-state interactions neglected;
  the expressions obtained take a relatively simple form involving atomic
  multipolar relaxation rates of the order of k = 0 and k = 2. The
  angular distributions for each case are combined with the frequency
  dependences to yield a three-component frequency redistribution
  function for an s-p-s transition, the components being a coherent term,
  a frequency-redistributed term with the same angular dependence as
  the coherent term, and an isotropic frequency-redistributed term.

---------------------------------------------------------
Title: A shock tube study of line broadening in a temperature range
    of 6100 to 8300 K.
Authors: Baur, J. F.; Cooper, J.
1977JQSRT..17..311B    Altcode:
  Line widths of the Ca(II) 3968 A and Na(I) 5890 A resonance lines
  broadened by electric microfields in a plasma were measured. A
  pressure-driven shock tube was used as the light source. Radiation
  from the equilibrium region behind the reflected shock wave was studied
  using a rapid scanning Fabry-Perot interferometer. Electron and argon
  atom densities of about 8 x 10 to the 16th and 1 x 10 to the 19th/cu cm,
  respectively, were achieved at the relatively low temperature of around
  7500 K by vaporizing a cesium powder that had been added to the shock
  tube as a solid aerosol in argon gas. The measured line widths were
  predominantly Stark broadened by the electrons and ions in the plasma,
  although Doppler, van der Waals, instrument function and optical depth
  effects had to be taken into account.

---------------------------------------------------------
Title: Correlations between Doppler and pressure broadening for the
    resonance interaction
Authors: Cooper, J.; Stacey, D. N.
1975PhRvA..12.2438C    Altcode:
  The correlation between Doppler and collisional broadening has been
  considered in detail for radiation in which the lower level of the
  transition is broadened by the resonance interaction. It is found
  that rather than a single Voigt profile, the profile of the radiation
  is essentially a sum of Voigt profiles. Although the widths of these
  profiles vary by some 40%, the over-all line shape is very close to
  the single Voigt shape obtained when correlation effects are neglected.

---------------------------------------------------------
Title: H<SUP> - </SUP> shape-resonance studies in an arc plasma
Authors: Ott, W. R.; Slater, J.; Cooper, J.; Gieres, G.
1975PhRvA..12.2009O    Altcode:
  Calculations by Macek have shown that the H<SUP>-</SUP>
  photoabsorption cross section should be affected by a shape
  resonance at 1129.5 Å. This experiment is an attempt to
  observe the resonance in emission according to the reaction
  e+H--&gt;[H<SUP>-</SUP>]<SUP>*</SUP>--&gt;H<SUP>-</SUP>+hν. The plasma
  is in a condition of local thermodynamic equilibrium and is generated
  by a stationary wall-stabilized hydrogen arc. With an axis temperature
  of 14000 K and 1 atm pressure, the H<SUP>-</SUP> free-bound continuum
  contributes only about 2% of the total radiation which is dominated in
  the 1130-Å region by the Ly-α wing. However, the peak of the shape
  resonance, according to Macek, should have a cross section about 25
  times greater than the continuous free-bound cross section; therefore,
  it should appear as a very noticeable 50% structure superimposed on
  the Ly-α wing. Except for some small features which are attributed to
  weak molecular emission, there is no obvious indication of the shape
  resonance in either deuterium or hydrogen spectra between 1105 and
  1135 Å. It is estimated that the minimum feature which could have
  been detected at 1129 Å was about 2% of the total signal.

---------------------------------------------------------
Title: On the effect of time-ordering for Lyman-alpha .
Authors: Greene, R. L.; Cooper, J.
1975JQSRT..15..991G    Altcode:
  Numerical calculations of the wings of the hydrogen Lyman-alpha line
  due to Stark broadening by electrons have been performed including time
  ordering effects. It is concluded that two recent calculations, which
  apparently disagree, are numerically correct within their respective
  approximations and their differences are explained.

---------------------------------------------------------
Title: A unified theory of Stark broadening for hydrogenic ions-I. A
    general theory (including time ordering).
Authors: Greene, R. L.; Cooper, J.; Smith, E. W.
1975JQSRT..15.1025G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Stark broadening tables for He I lambda 4922 Å.
Authors: Barnard, A. J.; Cooper, J.; Smith, E. W.
1975JQSRT..15..429B    Altcode:
  The Stark broadening of the He I 4922-A line and its forbidden
  components by both ions and electrons is calculated using a theory that
  includes ion dynamic effects. Tables are presented for temperatures
  from 5000 K to 40,000 K covering the density range 10 trillion to 10
  quadrillion per cu cm for both helium and hydrogen ionic perturbers.-

---------------------------------------------------------
Title: He I lambda 4922 profiles in B stars: calculations with an
    improved line broadening theory.
Authors: Mihalas, D.; Barnard, A. J.; Cooper, J.; Smith, E. W.
1975ApJ...197..139M    Altcode:
  Theoretical profiles for the He I A4922 line in B star spectra have
  been computed using the improved broadening theory of Barnard, Cooper,
  and Smith, and the level populations calculated by Auer and Mihalas
  from a simultaneous self-consistent solution of the coupled transfer
  and statistical equilibrium equations. The revised broadening theory
  yields excellent agreement with laboratory measurements of the width
  and intensity of the forbidden (2p ) transition. The results of this
  paper show that stellar profiles computed with the new theory are
  in excellent agreement with observed profiles, and the discrepancies
  between observation and theory that existed previously have now been
  removed. Subject headings: early-type stars - line profiles

---------------------------------------------------------
Title: A unified theory of Stark broadening for hydrogenic
    ions-II. Line wings.
Authors: Greene, R. L.; Cooper, J.
1975JQSRT..15.1037G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: A unified theory of Stark broadening for hydrogenic
    ions-III. Results for He II Lyman-alpha .
Authors: Greene, R. L.; Cooper, J.
1975JQSRT..15.1045G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: He I lambda 4471 profiles in B stars: calculation with an
    improved line-broadening theory.
Authors: Mihalas, D.; Barnard, A. J.; Cooper, J.; Smith, E. W.
1974ApJ...190..315M    Altcode:
  Theoretical profiles for the He I A4471 line in B-star spectra
  have been computed using an improved broadening theory of Barnard,
  Cooper, and Smith, together with level populations determined by a
  self-consistent solution by Auer and Mihalas of the coupled transfer
  and statistical-equilibrium equations. The broadening theory has been
  constructed to provide a more accurate description of the intensity
  and width of the forbidden (2p 3P0-4f 3F ) transition as measured
  in laboratory experiments. The results presented in this paper show
  that this revision of the broadening theory leads to computed stellar
  profiles which are in much better agreement with observed profiles
  than any previously obtained. Subject headings: early-type stars -
  line profiles

---------------------------------------------------------
Title: Correlation effects in the theory of combined Doppler and
    pressure broadening - I. Classical theory.
Authors: Ward, J.; Cooper, J.; Smith, E. W.
1974JQSRT..14..555W    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The broadening of He I lines including ion dynamic corrections,
    with application to lambda 4471 Å.
Authors: Barnard, A. J.; Cooper, J.; Smith, E. W.
1974JQSRT..14.1025B    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Redistribution of Resonance Radiation. 11. the Effect of
    Magnetic Fields
Authors: Omont, A.; Smith, E. W.; Cooper, J.
1973ApJ...182..283O    Altcode:
  Previously obtained results for scattering of radiation in the presence
  of collisions are restated in a density matrix formalism which employs
  an irreducible-tensor description of the radiation field. This formalism
  is particularly useful for problems associated with radiative transfer
  theory. The redistribution is then extended to include the effect of
  a weak magnetic field. By averaging over a finite bandwidth which is
  on the order of the Doppler width, simplified expressions of physical
  significance for the scattering in the Doppler core and the Lorentz
  wings are obtained. Expressions are also obtained for the corresponding
  source function of radiative transfer theory. Subject headings:
  magnetic fields - polarization - radiative transfer

---------------------------------------------------------
Title: Satellites to LYMAN-a due to Protons
Authors: Stewart, J. C.; Peek, J. M.; Cooper, J.
1973ApJ...179..983S    Altcode:
  Line broadening of the wings of La is calculated by using accurate H2 +
  wave functions. Of particular interest are the linelike satellites which
  appear prominently at 1233.5, 1240.5, and 1404.9 A. Subject headings:
  line formation - line profiles - spectra, ultraviolet

---------------------------------------------------------
Title: An analysis of the unified and scalar additivity theories of
    spectral line broadening.
Authors: Smith, E. W.; Cooper, J.; Roszman, L. J.
1973JQSRT..13.1523S    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Hydrogen Stark-Broadening Tables
Authors: Vidal, C. R.; Cooper, J.; Smith, E. W.
1973ApJS...25...37V    Altcode:
  Tables of Stark broadening of the first four Lyman lines and the
  first four Balmer lines of hydrogen are presented. They are based on a
  recently developed "unified theory" of line broadening which generates
  normalized profiles covering the entire profile from the impact limit
  in the line center to the quasi-static limit in the line wings. The
  tables are presented in a convenient form for accurate numerical
  interpolation. Subject heading: line profiles

---------------------------------------------------------
Title: Redistribution of Resonance Radiation. I. The Effect of
    Collisions
Authors: Omont, A.; Smith, E. W.; Cooper, J.
1972ApJ...175..185O    Altcode:
  The techniques of modern line-broadening theory are used to investigate
  the scattering of polarized radiation in the rest frame of an atom
  undergoing collisions. The formulation explicitly includes both elastic
  and inelastic (quenching) collisions. When the lower state has zero
  width, a form for the redistribution function similar to that of Zanstra
  is obtained, but with the redistribution in the neighborhood of the
  resonance line being caused solely by elastic collisions. In the limit
  of no collisions, but with both levels of finite lifetime, the result
  of `veisskopf and Woolley is obtained. The effect of level-degeneracy
  is also explicitly included; in this case the results are a function
  of the polarization of the light and the different relaxation rates
  for the multipolar components of the atomic states.

---------------------------------------------------------
Title: Overlap of Argon Ion Spectra with Satellites to the Lyman-Alpha
    Lines of Carbon and Boron
Authors: Jalufka, N. W.; Cooper, J.
1972ApJ...171..647J    Altcode:
  A theta pinch has been employed to investigate satellites to the H-like
  and He-like ion resonance lines of boron and carbon. Identification
  of the spectra shows an overlap of the Ar ix, Ar xi, and Ar xii lines
  with the predicted satellite wavelengths, and it is concluded that many
  of the previously reported satellite lines are due to argon impurities.

---------------------------------------------------------
Title: Determination of Van der Waals broadening at temperatures of
    astrophysical interest.
Authors: Cooper, J.; Evans, J. M., Jr.
1972JQSRT..12..259C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: An impact theory for Doppler and pressure broadening -
    I. General theory.
Authors: Smith, E. W.; Cooper, J.; Chappell, W. R.; Dillon, T.
1971JQSRT..11.1547S    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: An impact theory for Doppler and pressure broadening -
    II. Atomic and molecular systems.
Authors: Smith, E. W.; Cooper, J.; Chappell, W. R.; Dillon, T.
1971JQSRT..11.1567S    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Non-adiabatic effects in Van der Waals broadening.
Authors: Stacey, D. N.; Cooper, J.
1971JQSRT..11.1271S    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Unified theory calculations of Stark broadened hydrogen lines
    including lower state interactions.
Authors: Vidal, C. R.; Cooper, J.; Smith, E. W.
1971JQSRT..11..263V    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Hydrogen Stark broadening calculations with the unified
    classical path theory.
Authors: Vidal, C. R.; Cooper, J.; Smith, E. W.
1970hsbc.book.....V    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Computed profiles of He I 5016 Å at high electron densities.
Authors: Barnard, A. J.; Cooper, J.
1970JQSRT..10..695B    Altcode:
  Profiles of He I 5016Åand its forbidden component have been calculated
  and are tabulated for electron densities from 3×10<SUP>16</SUP>
  to 6×10<SUP>17</SUP> cm<SUP>-3</SUP> and temperatures from
  10<SUP>4</SUP> to 8×10<SUP>4</SUP>°K. The ion broadening is treated
  in the quasistatic approximation and the electron broadening of the
  overlapping Stark components in the impact approximation. The effect
  of the broadening of the lower level by electrons has been taken into
  account, and intermediate states up to n = 6 have been included.

---------------------------------------------------------
Title: Non-thermal effects in Stark broadening.
Authors: Chappell, W. R.; Cooper, J.; Smith, E. W.
1970JQSRT..10.1195C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Hydrogen Stark broadening calculations with the unified
    classical path theory
Authors: Vidal, C. R.; Cooper, J.; Smith, E. W.
1970JQSRT..10.1011V    Altcode:
  The unified theory has been generalized for the case of upper
  and lower state interaction by introducing a more compact tetradic
  notation. The general result is then applied to the Stark broadening
  of hydrogen. The thermal average of the time development operator for
  upper and lower state interaction is presented. Except for the time
  ordering it contains the effect of finite interaction time between
  the radiator and perturbers to all orders, thus avoiding a Lewis type
  cutoff. A simple technique for evaluating the Fourier transform of
  the thermal average has been developed. The final calculations based
  on the unified theory and on the one-electron theory are compared with
  measurements in the high and low electron density regime. The unified
  theory calculations cover the entire line profile from the line center
  to the static wing and the simpler one-electron theory calculations
  provide the line intensities only in the line wings.

---------------------------------------------------------
Title: Unified Classical-Path Treatment of Stark Broadening in Plasmas
Authors: Smith, Earl W.; Cooper, J.; Vidal, C. R.
1969PhRv..185..140S    Altcode:
  A theoretical treatment of spectral line broadening in plasmas is
  developed using classical-path methods. This treatment unifies certain
  aspects of the familiar impact, one-electron, and relaxation theories
  to produce results which are valid from the line center to the far line
  wings where the electrons may behave quasistatically. Calculations of
  the Lyman-α line of hydrogen are used to illustrate the theory.

---------------------------------------------------------
Title: Electron-Impact Broadening of Isolated Lines of Neutral Atoms
    in a Plasma. I
Authors: Cooper, J.; Oertel, G. K.
1969PhRv..180..286C    Altcode:
  This paper deals with the generalized impact theory for electron
  broadening of isolated spectral lines emitted by neutral atoms in a
  plasma. The existing theory is improved by quantitative evaluation of
  the second-order (quadrupole) term in the multipole expansion including
  broadening of the lower level and interference effects, by approximate
  inclusion of the "back reaction" of atom on perturber in inelastic
  collisions through symmetrization with respect to initial and final
  perturber states, and by corrections to the broadening functions in
  the classical-path approximation. While the quadrupole contribution is
  normally a small correction, it is shown that it may, in principle,
  dominate the weak collision broadening in some situations even when
  the multipole series converges; however, strong collisions will always
  dominate in this case. Numerical results of the improved theory are
  given for the half-widths at half-maximum of some helium i lines,
  and the effects of the corrections are evaluated.

---------------------------------------------------------
Title: Electron correlations in Stark broadening.
Authors: Chappell, W. R.; Cooper, J.; Smith, E. W.
1969JQSRT...9..149C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: On Strong Collisions in Hydrogenic Line Broadening
Authors: Shen, K. Y.; Cooper, J.
1969ApJ...155...37S    Altcode:
  The degeneracy of hydrogenic states is used to sum approximately
  the S-matrix to all orders in Stark- broadening calculations. It is
  found that the usual strong-collision cutoff for lower lines should
  represent a reasonable approximation. However, there could be a
  significant difference between our results and previous calculations
  for transitions among levels with large principal quantum numbers

---------------------------------------------------------
Title: 10. The Broadening of He I 4471 A and its Forbidden Components
Authors: Barnard, A. J.; Cooper, J.; Shamey, L. J.
1969LIACo..15...89B    Altcode: 1969MSRSL..17...89B
  No abstract at ADS

---------------------------------------------------------
Title: Stark broadening of the Na I 5682 - 88 A and 4978 - 82 A lines.
Authors: Oettinger, P. E.; Cooper, J.
1969JQSRT...9..591O    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Calculated Profiles of He I 4471 and 4922 A and their Forbidden
    Components
Authors: Barnard, A. J.; Cooper, J.; Shamey, L. J.
1969A&A.....1...28B    Altcode:
  The proffles of He 14471 and 4922 A and their forbidden components have
  been calculated and are tabulated for electron densities in the range
  1014 to 1017 cm-8, and for temperatures from 5000 to 40000 0K. The
  ion broadening is treated in the quasistatic approximation and the
  electron broadening of the overlapping Stark components in the impact
  approximation. Stark parameters are also tabulated from which proffles
  may be obtained for densities below 10^14 cm-8.

---------------------------------------------------------
Title: The broadening of He I 4471 Å and its forbidden components.
Authors: Barnard, A. J.; Cooper, J.; Shamey, L. J.
1969MSRSL..25...89B    Altcode: 1969tisa.conf...89B
  No abstract at ADS

---------------------------------------------------------
Title: Plasma spectroscopy
Authors: Cooper, J.
1966RPPh...29...35C    Altcode:
  No abstract at ADS