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Relativistic Many-Body Bound Systems: Electromagnetic Properties

Description: Report presenting the formulae for the calculation of the electron scattering form factors, and of the static magnetic dipole and electric quadrupole moments, of relativistic many-body bound systems. The framework, given in NBS Monograph 147, is relativistic quantum field theory in the Schrodinger picture ; the physical particles, i.e. the solutions of the interacting fields, are given as linear combinations of the solutions of the free fields, called the parton fields. The parton-photon interaction is taken as given by minimal coupling, p -> p - eA ; in addition the contribution of the photon-vector meson vertex of the vector dominance model is derived.
Date: April 1977
Creator: Danos, Michael & Gillet, Vincent

The Role of Standard Reference Materials in Measurement Systems

Description: Report is a guide to Standard Reference Materials (SRM's) and should be useful to all users of SRM's particularly those in countries developing national measurement systems. It is not intended to be an exhaustive description of the NBS-SRM program, but rather a review of the role SRM's play in the measurement system, how SRM's are certified, and what the certification means. To illustrate the use of SRM's, several selected industries are described in which SRM's have made significant contributions.
Date: January 1975
Creator: Cali, J. P.; Mears, T. W.; Michaelis, R. E.; Reed, W. P.; Seward, R. W.; Stanley, C., L. et al.

Liquid-in-Glass Thermometry

Description: Report containing information of general interest to manufacturers and users of liquid-in-glass thermometers. This report supersedes Monograph 90. Instructions explaining how to submit a thermometer to the National Bureau of Standards for calibration are provided, and the techniques and equipment, such as stirred liquid comparison baths, used in the calibration procedures are described. A discussion of important principles of acceptable thermometer design and factors affecting their use is included. Listed are tables of tolerances reflecting good manufacturing practices and reasonably attainable accuracies expected with liquid-in-glass thermometers. The calculation of corrections for the temperature of the emergent stem is given in detail for various types of thermometers and conditions of use.
Date: January 1976
Creator: Wise, Jacquelyn A.

Graphical Recoupling of Angular Momenta

Description: Report presenting a diagrammatic method for solving angular momentum recoupling problems. It is shown that a few graphical elements with a set of rules for their use lead to the solution of many types of recoupling problems in an intuitive and systematic way. Several examples are given together with exercises to develop the reader's facility with the method.
Date: October 1973
Creator: Lehman, D. R. & O'Connell, J. S.

Interactions of High Energy Particles With Nuclei

Description: Report discussing elastic scattering and diffractive production processes induced in nuclear targets by high energy projectiles. Special attention is paid to the interaction of high energy hadrons and photons. The common features of all these processes are emphasized throughout the article: The multiple scattering and shadowing processes inside of the target nuclei. An effort is made to develop a unified way of treating nuclear interactions of particles which are either hadrons or exhibit some hadronic components in such interactions.
Date: September 1975
Creator: Czyz, Wieslaw

Analysis of Optically Excited Mercury Molecules

Description: Report presenting new measurement techniques used to obtain potential curves, f-values, and kinetic behavior for Hg2. The Hg2 molecule is representative of a class of molecules which have dissociative ground states and bound excited states. It can therefore be used as a prototype of this class of molecules which are of interest as potential new laser candidates. Because of the non-bound ground state, standard absorption spectroscopic techniques cannot be used to obtain the necessary information about the excited states.
Date: January 1975
Creator: Drullinger, R. E.; Hessel, M. M. & Smith, E. W.

The Effect of Time Ordering on the Lyman α Profile

Description: Report investigating the effects of time-ordering over the complete line profile using a unified theory of spectral line broadening previously developed. The behavior of the time-ordered thermal average and un-time-ordered thermal average are compared. The Fourier transform of the thermal average is obtained analytically. Calculations for the line profile of the Lyman-[functional symbol alpha] line of hydrogen are presented and are representative in that the full thermal average is replaced by the thermal average with the electron velocity distribution approximated by f(v)=[functional symbol alpha] (v-vav) where vav is the thermal velocity for the plasma in question.
Date: June 1971
Creator: Godgrey, J. T.; Vidal, C. R.; Smith, E. W. & Cooper, J.

Reference Tables for Low-Temperature Thermocouples

Description: Report discussing the completed experimental program of the low-temperature reference tables for the commonly used thermocouples. Details of the experimental system, instrumentation, data analysis, error analysis, and materials tested are given in order to allow the user to better evaluate and apply the results.
Date: June 1972
Creator: Sparks, Larry L.; Powell, Robert L. & Hall, William J.

Thermocouple Reference Tables Based on the IPTS-68: Reference Tables in Degrees Fahrenheit for Thermoelements versus Platinum (Pt-67)

Description: Report presenting tables as a supplement to those given in NBS Monograph 125. Tables were calculated from the power series expansions presented in that Monograph. They are based upon the absolute electrical units and the International Practical Temperature Scale of 1968 (IPTS-68). Reference tables for several thermoelements versus platinum (Pt-67) are given with values of the thermoelectric voltage as a function of temperature in degrees Fahrenheit. Only tables for standard letter-designated thermoelements are included.
Date: March 1975
Creator: Powell, Robert L. & Burns, George W.

A High-Dispersion Spectral Analysis of the Ba II Star HD 204075 (ζ Capricorni)

Description: Report discussing a double differential curve of growth analysis for the Ba II star S Capricorni. Both the sun and � Virginis (G9 II-III) were used as comparison stars. The observational material consists of equivalent widths, central depths, and half-widths for 1100 spectral lines measured on direct-intensity tracings of plates obtained by J. L. Greenstein at the coude focus of the 200-in telescope. The plates cover the spectral regions 3880-4825 A and 5100-6720 A at reciprocal dispersions of 2.3 and 3.4 A/mm, respectively. Atmospheric abundances have been derived for 37 elements.
Date: March 1971
Creator: Tech, Jack L.

The Calculation of Rotational Energy Levels and Rotational Line Intensities in Diatomic Molecules

Description: Report describing procedures for making quantum mechanical calculations of rotational energy levels and rotational line intensities in diatomic molecules. The procedures are illustrated by sample calculations. A familiarity with the material of this report should enable a practicing electronic spectroscropist to carry out, though in a rather mechanical way, his own theoretical calculations for molecules under experimental investigation.
Date: June 1970
Creator: Hougen, Jon T.

Hydrogen Stark Broadening Calculations With the Unified Classical Path Theory

Description: Report discussing the case of upper and lower state interaction introduced by a unified theory using 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. 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.
Date: May 1970
Creator: Vidal, C. R.; Cooper, J. & Smith, E. W.

Photonuclear Reactions

Description: Report discussing photonuclear reactions in the approximate energy range 10 to 30 MeV. Various sum rules are discussed and applied to experimental data. Several different theories are described and their predictions compared with experiment, and as often as possible open questions and discrepancies are pointed out.
Date: August 1970
Creator: Hayward, Evans

Survey of Micromanometers

Description: This survey is concerned with instrumentation for measuring pressures from about 0.001 to 50mm of mercury (0.13 to 6650 Nm-2), described in publications during the years 1900-1968. U-tube micromanometers and diaphragm-capacitance gages are treated in considerable detail. Other instrumentation described includes gas column manometers; elastic element micromanometers with optical, inductance, resistance wire, strain gage, and vacuum tube transducers; piston gages; vane gages; and centrifugal micromanometers. The measurement of dynamic pressure, atmospheric pressure oscillations, low vapor pressure, and calibration techniques are discussed. Schematic diagrams of approximately 70 instruments are included. References to the sources of information and available performance data are given.
Date: 1970
Creator: Brombacher, W. G.

Geometrical Considerations and Nomenclature for Reflectance

Description: Report presenting a unified approach to the specification of reflectance, in terms of both incident- and reflected- beam geometry. Nomenclature to facilitate this approach is proposed. Nomenclature for categorizing and specifying reflectance quantities for a variety of different beam configurations (both incident and reflected beams) is described, and all are defined and interrelated in terms of the bidirectional reflectance-distribution function. The conditions under which the formalism can be applied, including situations involving considerable sub-surface scattering, are carefully established. The entire treatment is limited to the domain of classical geometrical-optics radiometry and does not take into account interference and diffraction phenomena, such as are frequently encountered with highly coherent radiant flux.
Date: October 1977
Creator: Nicodemus, F. E.; Richmond, J. C.; Hsia, J. J.; Ginsberg, I. W. & Limperis, T.

Measurement Assurance for Gage Blocks

Description: Report discussing the philosophy of measurement assurance and the three levels of measurement assurance programs. The measurement assurance programs are outlined to show how control over the measurement process can be maintained and how the offset (or systematic error) from the unit of length maintained by the National Bureau of Standards ban be made negligible. This monograph is intended for those who need to know on a continuing basis the uncertainty of their gage block calibration procedure.
Date: February 1979
Creator: Croarkin, Carroll; Beers, John & Tucker, Clyde

Automatic Indexing: A State-of-the-Art Report

Description: Report issued by the U.S. National Bureau of Standards discussing results of a survey conducted on automatic mechanized indexing and data processing. As stated in the introduction, "it has concentrated on the major developments in and related demonstrations of automatic indexing potentialities. Examples are also given of indexes compiled by machine and of potentially related research efforts in such areas as natural language text searching, statistical association techniques used for search and retrieval, and proposed systems for concept processing" (p. 1). This report includes an illustration.
Date: February 1970
Creator: Stevens, Mary Elizabeth

Geometrical Considerations and Nomenclature for Reflectance

Description: Report issued by the U.S. National Bureau of Standards discussing specifications of reflectance and proposed nomenclature. As stated in the introduction, "this monograph presents a unified approach to the specification of reflectance in relation to the beam geometry of both the incident and the reflected flux in any reflectometer or in any application of measured reflectance data" (p. 1). This report includes illustrations.
Date: October 1977
Creator: Nicodemus, F. E.; Richmond, J. C.; Hsia, J. J.; Ginsberg, I. W. & Limperis, T.