Generalization of ratio estimate for population total
Estimating total Y for finite population with unknown values
Walsh, J. E.↗
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Exact intervals and test for mean of symmetrical population when one sample value possibly an outlier
Confidence intervals and significance tests for mean of symmetrical population with smallest or largest outlier observation
Walsh, J.↗
Comparison of tektite population polygons of bulk specific gravity, true material specific gravity, and refractive index
Australian tektites population polygons of bulk specific gravity and refractive index, indicating variations in chemical composition
Scheiber, L. C.↗
GaAs-laser-induced population inversion in the ground-state hyperfine levels of Cs133
Population inversion in Cs133 ground state hyperfine levels, using CW GaAs laser at 77 K for optical pumping
Alley, C. O.↗
Variable abyssal basalt populations and their relation to sea-floor spreading rates
Variable abyssal basalt populations, considering chemical analyses variations for ridges as function of ocean floor spreading rate
Bass, M. N.↗
Population inversion of A. U. V. atomic line in recombining plasma nozzle flow
Arc heated plasma expansion through nozzle, observing population inversion of neutral carbon self-absorption UV atomic line
Bowen, S. W.↗
Two populations of aliphatic hydrocarbons of teratoma and habituated tissue cultures of tobacco
Internal short chain alkane populations of paraffinic hydrocarbons in tobacco teratoma and habituated tissue cultures
Laseter, J. L.↗
Anisotropy characteristics of low energy cosmic ray population of solar origin
Solar low energy cosmic ray population anisotropy from satellite observations during flare event, describing rise time, decay, field alignment and time constant
Allum, F. R.↗
Comments on the instability strip for halo population variables
RR Lyrae stars instability strip for halo population variables, presenting linear nonadiabatic approximate pulsation calculations with emphasis on blue edges location in H-R diagram
Huchra, J.↗
Population inversion calculations using near resonant charge exchange as a pumping mechanism
Near resonance charge exchange between ions of a large ionization potential gas such as helium or neon and vapors of metals such as zinc, cadmium, selenium, or tellurium has produced laser action in the metal ion gas. The possibility of obtaining population inversions in near resonant charge exchange systems (Xe-Ca, Xe-Mg, Xe-Sr, Xe-Ba, Ar-Mg, N-Ca) was investigated. The analysis is an initial value problem that utilizes rate equations for the densities of relevant levels of the laser gas (Ca, Ba, Mg, or Sr) and an electron energy equation. Electron excitation rates are calculated using the Bohr-Thomson approximation for the cross section. Approximations to experimental values of the electron ionization cross section and the ion-atom charge exchange cross section are used. Preliminary results have been obtained for the Ca-Xe system and show that it is possible to obtain gains greater than 10 to the 14th power/m with inversion times up to 8x10 to the minus 7th power second. A possible charge exchange laser system using a MPD arc plasma accelerator is also described.
Chubb, D. L.↗
The population of high atomic levels at low temperatures.
Calculated coefficients relating the population in level n to its value in equilibrium are presented for various atomic levels under conditions of low temperature, density, and thermal radiation fields that may be expected in the interstellar medium. A thermal continuum such as that produced by an H II region is found to substantially change both the departure coefficients and their slope under conditions of low density.
Dupree, A. K.↗
Interval scanning photomicrography of microbial cell populations.
A single reproducible area of the preparation in a fixed focal plane is photographically scanned at intervals during incubation. The procedure can be used for evaluating the aerobic or anaerobic growth of many microbial cells simultaneously within a population. In addition, the microscope is not restricted to the viewing of any one microculture preparation, since the slide cultures are incubated separately from the microscope.
Casida, L. E., Jr.↗
Magnetospheric particle populations.
Significant results of magnetospheric charged particle measurements conducted within the past two years are reviewed in an attempt to provide a general description of relationships among particle populations in the magnetosheath, plasma sheet, extraterrestrial ring current region, electron trough, pseudotrapping region, and stable-trapping region. Special attention is given to the characteristics of protons, electrons, alpha particles, and particles with charge greater than three in the stable trapping region.
Vette, J. I.↗
The chemical composition of population I stars.
A comparison of observed and theoretical mass-luminosity relations for unevolved stars in high-mass eclipsing binary systems and in low-mass visual binary systems is used to find the hydrogen and metals abundances of Population I stars: X = 0.69 plus or minus 0.12 and Z = 0.036 plus or minus 0.039. Alternatively, by adopting Z = 0.03 plus or minus 0.01, one finds X = 0.71 plus or minus 0.03. Limitations of the method are discussed briefly.
Stothers, R.↗
A dual extremum principle for a population equation
A dual extremum principle for the Verhulst-Pearl population equation is constructed using a complementary variational technique. The dual formulation utilizes a minimum principle recently developed by Leitmann to convert the functional optimization problem into a parameter optimization problem.
Chan, W. L.↗
Measurement of the photoionization cross section from the laser-populated 3D metastable levels in barium
Measurements of the absolute photoionization cross section from the 6s5d 3D metastable level of barium are presented. The 3D levels were selectively populated with a high-power tuneable dye laser. The number density was determined by observing the resulting depopulation of the ground state when pumping occurred.
Carlsten, J. L.↗
Absorption spectrum of the laser-populated 3D metastable levels in barium
This paper deals with the details of the absorption spectrum of the 3D metastable term in barium. The 3D term was selectively populated with a tuneable dye laser. The fundamental triplet series (6s5d 3D-6snf 3F) is identified and extended out to n = 32. In addition, the absolute photoionization cross section was measured at 303 nm. The relative cross section from 303 to 250 nm was also measured with the absolute scale set by the measurement at 303 nm and was found to be nearly constant in the wavelength region measured.
Carlsten, J. L.↗
Asteroid collisional evolution - Evidence for a much larger early population
The present population of asteroids is a remnant of a vastly larger one that contained perhaps a planetary mass, dominantly distributed in planetesimals approximately 500 kilometers or less in diameter. It constituted a large reservoir of objects that plausibly were responsible for cratering the moon, Mars, and Mercury. Much asteroidal dust may have accumulated on Mars and other planets.
Chapman, C. R.↗