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MEASUREMENTS AND STANDARDS IN

PLASMA-PHYSICS AND ASTROPHYSICS

AT THE NATIONAL BUREAU OF STANDARDS

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
THE NATIONAL BUREAU OF STANDARDS

Functions and Activities

The functions of the National Bureau of Standards are set forth in the Act of Congress, March

3, 1901, as amended by Congress in Public Law 619, 1950. These include the development and

maintenance of the national standards of measurement and the provision of means and methods for making measurements consistent with these standards; the determination of physical constants and

properties of materials; the development of methods arid instruments for testing materials, devices,

and structures; advisory services to government agencies on scientific and technical problems; in- vention and development of devices to serve special needs of the Government; and the development

of standard practices, codes, and specifications. The work includes basic and applied research,

development, engineering, instrumentation, testing, evaluation, calibration services, and various

consultation and information services. Research projects are also performed for other government

agencies when the work relates to and supplements the basic program of the Bureau or when the

Bureau's unique competence is required. The scope of activities is suggested by the fisting of

divisions and sections on the inside of the back cover.

Publications

The results of the Bureau's work take the form of either actual equipment and devices or pubfished papers. These papers appear either in the Bureau's own series of publications or in the journals

of professional and scientific societies. The Bureau itself publishes three periodicals available from

the Government Printing Office: The Journal of Research, published in four separate sections,

presents complete scientific and technical papers; the Technical News Bulletin presents summary

and preliminary reports on work in progress; and Basic Radio Propagation Predictions provides

data for determining the best frequencies to use for radio communications throughout the world.

There are also five series of nonperiodical publications: Monographs, Applied Mathematics Series,

Handbooks, Miscellaneous Publications, and Technical Notes. Information on the Bureau's publications can be found in NBS Circular 460, Publications of the

National Bureau of Standards ($1.25) and its Supplement ($1.50), available from the Superintendent

of Documents, Government Printing Office, Washington 25, D.C.
NATIONAL BUREAU OF STANDARDS

technical ^Ttote

59

JULY 1960

MEASUREMENTS AND STANDARDS IN

PLASMA-PHYSICS AND ASTROPHYSICS

AT THE NATIONAL BUREAU OF STANDARDS

Edited by

Lewis M. Branscomb, Coordinator

NBS Plasma-Physics and Astrophysics Program

NBS Technical Notes are designed to supplement the Bureau's regular publications program. They provide a means for making available scientific data that are of

transient or limited interest. Technical Notes may be

listed or referred to in the open literature. They are for sale by the Office of Technical Services, U. S. Department of Commerce, Washington 25, D. C.

DISTRIBUTED BY

UNITED STATES DEPARTMENT OF COMMERCE

OFFICE OF TECHNICAL SERVICES

WASHINGTON 25, D. C.

Price $1.00

TABLE OF CONTENTS

Page

I. Introduction 1 II. Background 2

III. Description of the Program Area 4

A. Atomic Properties 5

B. Gases under Near-Equilibrium Conditions, or in

Idealized Configurations 8

C. Phenomena Far from Equilibrium; As trophysical and

Geophysical Applications 11

IV. Appendix

A. Bibliography 14

1. Atomic and Molecular Properties 14

a. Atomic Energy Levels and Spectra 14

b. Molecular Spectra 15

c. Line Shapes, Intensities, and Transition

Probabilities 16

d. Photoionization, Photodetachment 17

e. Negative Ion Binding Energies 18

f

.

Collision Cross Sections 18

2. Transport Properties and High Temperatures 19

a. Theory of Non-Equilibrium Rate Processes and

Mechanics 19

b. Chemical Kinetics, Experimental 20

c. Gas Phenomena Chemiluminescence 21

d. Spectroscopic Temperature Measurements 21

e. Thermodynamic Properties of Ionized Gas 22

3. Plasma Physics and Astrophysics 23

a. Plasma Physics 23

b. Astrophysics 23

c. Solar Physics 24

d. Upper Atmosphere Physics - Airglow and Aurorae. . 24

e. Ionosphere 25

B. List of Participants 26

MEASUREMENTS AND STANDARDS IN PLASMA- PHYSICS AND ASTROPHYSICS

at the National Bureau of Standards

Abstract; The National Bureau of Standards has embarked on

a special program to unify and accelerate its research on hot

gases. This work will provide data and theory presently re- quired for the quantitative interpretation of astrophysical

and geophysical observations and the measurement of properties

of plasmas in the laboratory. The data, measurement techniques, and theoretical methods of analysis draw on activities

in the fields of atomic and molecular physics, statistical

mechanics and thermodynamics, fluid mechanics, and theoretical

astrophysics and geophysics. Both the Washington and Boulder

laboratories of the NBS are participating. This Note describes

the technical objectives of the program and includes in appendices a selected list of papers published at the NBS for the

period 1955-1959 and a partial list of Bureau participants.

I. INTRODUCTION

A number of major national programs in applied technology - such as thermonuclear power, space exploration, rocket propulsion, hypersonic

aerodynamics, and ionospheric communications - have in common their dependence upon the solution of basic problems in a rapidly growing area

of physics: the physics of very hot gases which are often not in a state of local thermodynamic equilibrium. However, progress in understanding the complicated processes in such high- temperature gases has to

date been slow and sporadic partly because problems have been attacked

independently from separate points of view in a number of different fields.

To alleviate this difficulty, the National Bureau of Standards has

initiated efforts to strengthen and unify all its research programs which

deal with the properties of hot gases and their accurate measurement. The

purpose of this Technical Note is to describe the program which is underway

and to list recent significant papers published by the senior scientific

staff associated with these activities. From time to time, other Notes

may be published to keep the bibliography of publications up to date.

Although no central reprint file will be kept, in most cases reprints

can be obtained from the authors.

Since the NBS program in this area is intended to meet the needs of

astrophysicists, aeronomists, plasma physicists^, and others, suggestions

on the direction which the program should take will be welcomed.

For example, gaseous electronics, astrophysics, chemical kinetics,

aerodynamics, high temperature physics, atomic spectroscopy and collision theory, and magnetohydrodynamics.
-2-

II. BACKGROUND

Engineering and technical applications in the fields mentioned

require accurate measurements on the essential material involved:

the hot plasma. Because this high- temperature gas is not usually

in local thermodynamic equilibrium, the parameters usually invoked

to describe gases - temperature, pressure, density, and electrical

conductivity - are either ill defined or must be used in restricted

senses. It is a general property of such plasmas, for example, that

a single temperature parameter cannot be used to characterize the

partition of energy over the many states of the system. Thus, a large number of collective and atomic properties of the gas require

clear characterization and accurate measurement for scientific

progress to be made.

The mission of the National Bureau of Standards is to "provide

the central basis for a complete consistent system of physical

measurement adequate for the expanding national activity in scientific research." In this case, such a basis can be provided only

by making an accurate determination of the important physical

parameters. These parameters include transition probabilities,

transport properties, the mechanism of radiation propagation through

non-equilibrium gases, and the mechanism of energy degradation of

radiation. To be fully useful, these precision determinations must

be accurately and consistently related to the national standards of

physical measurement. Further, any such system of measurement must

be completely coupled to the analytical methodology used in interpreting the measurements.

For example, in determining transition probabilities, the first

objective will be to find how these probabilities can be measured

with maximum accuracy in terms of the basic standards of radiation.

This procedure is required to meet the demands of the current

program for precise data and to assist other laboratories in making

measurements related as closely as possible to the fundamental

standards.

To relate the many fields of specialization, a more basic

approach is needed, which in essence creates a single broad problem

and treats this problem from a systematic and quantitative point

of view. The long-range objective is therefore the solution of the

"many-body problem" of modern atomic physics in its full generality.

Required to accomplish this goal are precision measurements and

calculations of the many atomic and collective parameters which

govern the behavior of the hot plasma or gas and which provide the

diagnostic tools for a description of the state of the gas. Next,

a characterization of the behavior of the gas in the correct

theoretical framework must be accomplished without introducing

drastic simplifying assumptions.
-3-

Astronomers were the first to recognize the need for this

unified approach, which characterizes the field of astrophysics.

Looking at ionized gases which cover enormous ranges of temperature

and in which energy is dissipated by Shockwaves, radiation, and

many types of collisions, the astrophysicists are finding that they

are forced by their observations to come to grips with the essential

problem and to reduce their reliance on the assumed applicability

of equilibrium thermodynamics.

In applying plasma physics to the control of thermonuclear

reactions, an astrophysical environment - extremely hot gases with

high energy dissipation - is complicated by a highly transitory

phenomenon as well. Here accurate spectroscopic parameters, reaction

rates, and methods for dealing with this many-body problem are even more desperately needed. Hence, it seems appropriate to take

the name "plasma and astrophysics" to characterize this synthesis

of specializations dealing with hot gases not in local thermodynamic

equilibrium, even though this research are£ is equally applicable

to ionospheric physics, aerodynamics, and the other fields mentioned

above.

The appropriateness of undertaking at the National Bureau of

Standards a unified approach to the problem of gases in a state

of non-LTE2 i s evident from the consequences of replacing the

thermodynamic approach (in which energy levels and statistical

weights are the only microscopic parameters required) by detailed

rate theories (in which transition probabilities and all of the

relevant collision cross sections must be known). The demand for

basic physical information then becomes enormous, and a corresponding emphasis is placed on accuracy. However, in most cases

adequate measurement techniques do not exist. A long-range experimental program to develop new measurement standards is therefore

required along with a closely interrelated theoretical program on both the general problem and the specialized fields of application.

This theoretical work is also greatly needed for the space sciences

to promote full utilization of the enormous amount of new observational material being acquired through the rocket and satellite

programs and the new radio and optical telescopes.

The Bureau already has heavy commitments in important aspects

of the plasma and astrophysics area through its basic programs

on atmospheric, ionospheric, and solar phenomena; the physical

properties of atomic systems and high temperature gases; and

2

LTE: An abbreviation for "local thermodynamic equilibrium."
-4-

propagation of radiofrequency radiation through plasmas. However,

the breath taking speed with which the results of modern atomic

physics are applied to engineering projects of major national consequence challenges the Bureau to strengthen and coordinate a unified

interdivisional and interlaboratory program on measurements and

standards in plasma and astrophysics.

The basic motivation behind this entire program is to obtain

accurate data and acquire an appropriate understanding of physical

behavior which will assist other laboratories and observatories in

understanding the properties of non-LTE hot gases as they occur in

nature. It is not sufficient, however, to develop measurement

standards and methods of analysis without subjecting them to the

test of practical application. Indeed, the application of the data

to suitable practical situations forms the ultimate test of the

scientific method for initially generating reliable and useful data.

In addition, the fundamental data and theory are more readily utilized

by other scientific laboratories when their value has been demonstrated in application. Through the establishment of collaborative

programs with allied scientific institutions such as the High

Altitude and Sacremento Peak Observatories, the Diamond Ordnance Fuze

Laboratories, and certain universities, the Bureau hopes to see the results of its research utilized most effectively. We also

depend strongly on collaboration with similar programs in other

countries. Through careful coordination and planning these

laboratories and observatories have in many cases divided up

the enormous amount of work and cooperatively seek a common objective.

III. DESCRIPTION OF THE PROGRAM AREA

The basic problems in a plasma program are characterizing

the gas, which is not in local thermodynamic equilibrium, and

providing adequate standards of measurement to describe the gas.

In such a gas, net transport of energy across the boundaries is

not necessarily negligible compared to the energy stored. Furthermore, this transport generally occurs more rapidly through certain

degrees of freedom than in others, so that the different degrees

of freedom of the gas are not in equilibrium with one another.

While it may be possible to characterize the energy distribution

within a given degree of freedom by one temperature parameter,

other degrees of freedom which are weakly coupled to the first

may be characterized by radically different "temperatures;" in

fact, it may not be possible to use the concept of temperature

at all, even in this restricted sense. Thus, in the absence of

LTE, not only must the energy states of all components of the
-5-

system and their populations be known, but also the reaction rates

and transition probabilities of the most important processes.

The present and the proposed plasma and astrophysics research

programs cut across divisional lines of organization and touch very

closely other major Bureau programs - for example, high- temperature,

microwave, radiometric, wavelength, geophysical, ionospheric, and

solar research. It is neither easy nor advantageous to draw a hard

line of division; indeed, it is the very close relationship of the

plasma and astrophysics research program to these other fundamental

standards and observational programs that makes this overall program

so challenging and potentially fruitful.

The plasma and astrophysics program is particularly closely

related to the interdivisional high- temperature program. The hightemperature program is devoted to the study of the definition and

measurement of the properties of high-energy systems in thermodynamic

equilibrium. As temperatures rise above the 5- to 10-thousand degree

region, all materials are vaporized, and it becomes increasingly

difficult to maintain thermodynamic equilibrium because of the problem

of containing the hot material. In this very-high- temperature range,

thermodynamic equilibrium may only be approached, and then only in

a transient state. Here the high- temperature and the plasma- and

astrophysics programs become indistinguishable. For convenience,

the plasma and astrophysics areas may be arbitrarily separated by

the degree of departure from LTE or by at least one degree of

freedom in a system with an effective temperature above 10, 000°K

(1 ev). This temperature will usually result in an appreciable

degree of ionization. Many basic programs on atomic parameters

are equally important to both areas, particularly atomic energy

levels and transition probabilities.

The proposed program separates naturally into the following

three parts, which are logically related in a chain but which are nevertheless to be undertaken simultaneously: (A) a study of

atomic properties; (B) an investigation of gases under near- equilibrium or idealized conditions; and (C) a study of gases far

from thermodynamic equilibrium.

A. Atomic Properties

Atomic properties will be studied to provide all the microscopic parameters required to specify the interaction of individual

photons, electrons, atoms, and molecules in the energy region up

to 10 kev. Thus, attention is to be focussed on a comprehensive

program to provide energy levels; dissociation, ionization, and

activation energies; and all interaction cross sections and transition probabilities.
For a long time, the Bureau has carried out a basic program on

the atomic properties of high- temperature gases. The results of the

atomic energy levels program of the Spectroscopy Section have been

effectively applied in astronomical research for decades, but this

work has been geared primarily to the traditional requirements of

astrophysics. In the past, astrophysics has generally assumed equilibrium conditions, and accordingly has set highest priority on

energy level schemes, on wavelength standards, and relative f-values,

rather than on absolute transition probabilities and on thermal

collision cross sections. The plasma and astrophysics program re- quires substantial programs in all three of these areas. It is not

feasible to wait until the program on energy levels is completed to

attack the probability and cross section aspects. Absolute transition probabilities of spectral lines are required if spectroscopic

methods are to be used to determine the state of a gas in the absence

of LTE. The cross sections for absorption and emission of continuous

radiation through photoionization and photodetachment must also be

known.

A wide range of information is needed about the absolute cross

sections for simple collisional processes - such as a spectral

excitation and ionization by electron, ion, and atom impact - as well as about the cross sections for many non-radiative processes - such as elastic scattering, charge transfer, dissociative recombination, and associative detachment. It is particularly important to

develop theoretical tools for reliable prediction of these quantities.

This ability to predict is an essential goal for physical research,

for it permits information to be produced more quickly and completely,

and with greater versatility. The theoretical tools can also be

applied to situations in astrophysics which cannot be duplicated in

the laboratory.

Thus, there must be not only a strong program of experimental

research, but also a th eoretical program closely correlated with

it. Those experiments must be emphasized which are most likely to

lead to increased theoretical understanding. While all the elements

are relevant to the program, special emphasis should be given to

hydrogen, helium, carbon, nitrogen, oxygen, iron, and the light

metals because of their abundance and theoretical importance.

The program which is needed, and for which the facilities and

interests of the Bureau's Atomic Physics Division and parts of the

Heat Division are most appropriate, is outlined below:
-7-

1. Atomic and Molecular Energy Levels

a. Analyses of atomic spectra; revision of solar spectrum tables;

preparation of new multiplet tables; extensive observations of new

rare earth spectra in different states of ionization; investigation

of spectra in the vacuum ultraviolet region.

b. Completion of atomic energy levels work on rare earth spectra;

investigations of gaps in analyses of other selected spectra; ultraviolet solar spectroscopy; special hyperfine and radiofrequency

spectroscopy of astrophysical interest.

c. Analysis and compilation of important molecular electronic

spectra.

d. Determination of ionization potentials, which for the most

part require more vacuum ultraviolet work under the AEL program and

electron affinities.

e. Binding energy calculations.

f. Activation energy determinations for reactions of interest

in geophysics, astrophysics, and aerodynamics.

2. Transition Probabilities

a. Measurement of atomic transition probabilities for a broad

class of spectra and on an absolute quantitative basis.

b. Determination of natural line shapes and the influence of

Zeeman, Stark, and Paschen-Back effects on transition probability

and line shape.

c. Measurement of continuous absorption coefficients for photoionization, photodetachment, and free-free absorption; cross sections

for the reverse processes.

d. Development of fundamental radiation theory.

3. Collision Cross Sections

a. Studies of the excitation and ionization of atoms and ions

by electron impact, especially near threshold.

b. Investigations ot the elastic scattering of electrons by

atoms and ions
•8-

c. Heavy-particle collision studies: Collisional recombination;

attachment, mutual neutralization, charge transfer, associative

detachment, and similar ionic reactions; and excitation and ionization by fast atom impact.

d. Collisional line broadening and frequency shift investigations

from the microscopic point of view.

e. Studies of high- temperature chemical reactions and collision

cross sections involving neutral atoms, molecules, and surfaces,

including ablation, sputtering, and accommodation coefficients.

f. Development of fundamental collision theory.

Gases under Near-Equilibrium Conditions,

or in Idealized Configurations

Efforts are also underway to achieve greater physical insight

into high-temperature phenomena and subsequently to develop methods

of characterizing high- temperature gases not in local thermodynamic

equilibrium. This work, which will take the equilibrium state as the

point of departure, will include studies of spectroscopic and radiofrequency diagnostic methods; determinations of collective atomic

parameters which depend on many-body interactions or thermal interaction energies such as line shapes, recombination rate coefficients,

and thermodynamic properties at high temperatures; and development

of magnetohydrodynamic theory.

This work requires as a basis the values of the atomic parameters

for interactions between various energy states. For example, these

parameters are essential for the investigation of rate processes

characterizing interactions. This investigation in turn makes it

possible to specify both the types of ions present in a gas of given

chemical composition and the distribution functions giving the

occupation numbers of the various energetic states as functions of

electron temperature and electron density. As distribution functions

are given uniquely by the temperature and density only under conditions

of thermodynamic equilibrium, no knowledge of atomic interaction

parameters is required. When, however, there exists in the gas a flux of energy, the gas is, in general, not able to "relax" to the

LTE configuration, so that the LTE distribution functions are not

adequate to describe the gas. If, for example, a flux of non- radiative energy is the energy source, while the dissipation is

largely radiative, cyclic processes are established in the gas which

retains the non-LTE configuration. Under certain circumstances,

groups of energetic states may be strongly coupled among themselves.

This permits their relative description by an "effective" temperature,
=9 =

which, however, differs considerably from group to group , Under

other circumstances, the relative occupation numbers of each two

energy levels require a different " temperature" parameter. Such a variety of situations is encountered in glow discharges in the

laboratory, in the ionosphere, in the outer solar atmosphere, and

in other gaseous atmospheres encountered in astrophysics. All these

processes must be studied theoretically, experimentally, and observationally and the results of the three approaches combined to gain

physical insight and make progress.

High- temperature gases and plasmas are studied primarily by

optical and radiofrequency spectroscopy. The interaction of radiation

with a plasma is governed not only by the atomic properties of the

individual particles in the gas, but also by collective properties,

such as Holtzmark broadened spectral lines, plasma oscillations,

interaction of a plasma with long -wave length radiation, perturbation

of energy levels and transition probabilities by long-range in teractions, and so forth. These properties must be investigated in

"idealized" plasmas, whose state is well known whether it is or is

not near thermal equilibrium. Furthermore, it is desirable for many

purposes that such experimental plasmas be optically "thin" and

in collisional equilibrium, that is, that a small fraction of the

energy be dissipated through radiation. These conditions are often very difficult to achieve, for optical lines are often self

absorbed to some degree. The situation is even less promising in

the microwave continuum of ultra-high temperature plasmas, which are often completely opaque in the normally accessible frequency range.

This part of the program can be divided into three parts: The

technological development of methods to produce a hot, partially

ionized gas in the laboratory; laboratory diagnostic studies of this

plasma to provide thermodynamic parameters, such as electron temperature and electron density, and to lead to further understanding of

atomic phenomena such as line-broadening 3 and theoretical developments

necessary to synthesize and interpret experimental results. A

fourth aspect of great importance, the application of the experimental

and theoretical developments to observations of natural phenomena,

such as the ionosphere and solar atmosphere, falls mainly in part

C of this note, although no hard and fast division can be made. In

the laboratory programs, the Heat Division in Washington and the

Gaseous Physics Group in Boulder, Colorado, will have the most

extensive effort, with more limited participation from the

Mechanics and Applied Mathematics Divisions in Washington. The

Heat Division will contribute mainly to the thermodynamic aspect

by extending its high temperature program into the very-hightemperature range (10,000 to 10, 000, 000°K). The Boulder Laboratories'

experimental work will utilize extensive experience in microwave

probing and ionospheric physics. Parts B and C will be linked at

the Boulder Laboratories through the optical spectroscopy programs,
-10-

with its strong interrelation with the microwave diagnostics on one hand and the ionospheric and solar observations on the other. The

theoretical work on non-LTE astrophysics will provide a bridge between

the theoretical studies in this part of the program, and those

in section C. It should be emphasized that a large body of theory on the non-LTE configuration has been already developed in this

astrophysics program which is applicable both to the laboratory and

the astrophysical environment.

Fully ionized gases have special macroscopic dynamic properties

caused by their strong reactions to electric and magnetic fields.

The properties form the subject of an extensive and complex theory

in the currently developing field of magnetohydrodynamics. Here

again, the fundamentals of this theory are properly part of this

phase of the program, but its application to practical situations

(in which velocity fields and instabilities occur) falls into

part C. An outline of the studies of gases under near-equilibrium

or idealized conditions (part B) is presented below.

1. Sources of Plasmas for Quantative Laboratory Studies

a. Conventional plasma arc "thermometry:" Study of the effects

of transition probabilities on assessing the approach to LTE in the

arc.

b. Production of plasmas and high- temperature gases in conventional shock tubes; in shocks generated electromagnetically, as in

exploding wires, in magnetic shocks, and in resonating shock tubes;

development of high-speed microwave, spectroscopic, and optical

techniques; design of new methods of plasma generation suitable for

quantitative studies.

2. Plasma Diagnostics and Collective Atomic Parameters

a. Theoretical investigations and measurements of cross sec- tions and reaction rates for many-body interactions which are not

amenable to direct microscopic measurement - such as three -body

recombination, attachment, reassociation, and free-free absorption

and emission in fields of atoms and ions.

b. Experimental and theoretical studies of averaged or statistical atomic properties which cannot be studied by direct

microscopic measurement - such as electron and ion mobilities,

collision frequency, velocity-averaged two-body recombination and
-11-

attachment coefficients, and thermodynamic properties at ultra-high

temperatures . -*

c. Utilization of the above sources of plasmas in applying highspeed microwave methods to determine electron density, collision

frequency, and shock velocity: Studies of thermal and nonthermal

rf noise emission from plasmas related to rf noise standards.

d. Application of spectroscopic methods to determine line

shapes under suitably controlled conditions and to study the

broadening mechanisms; use of known transition probabilities to

determine distribution of atomic states.

e. New diagnostic methods, such as particle velocity analysis

by mass spectrometry; gamma-ray, X-ray, and neutron spectroscopy;

Cerenkov radiation from probing particle beams; electron beam probes;

and neutral beam attenuation.

f

Interactions of shock waves and plasmas with surfaces; influ- ences of wall materials.

3. Statistical, Molecular, and Hydrodynamic Theory

a. Non-equilibrium statistical mechanics, including the study

of many-body problems; the development of foundations for statistical mechanics, and the investigation of cooperative phenomena and

transport properties, including radiation fields.

b. Determination of the thermodynamic transport properties of

ionized gases through a study of long-range molecular forces and

relevant molecular properties.

c. Investigation of the fundamental aspects of the flow of an ionized gas through electric and magnetic fields, including kinetic

equations, electrical conductivity, and electrical hydrodynamics.

C. Phenomena Far from Equilibrium;

Astrophysical and Geophysical Applications

In this phase of the program, data on atomic properties and

on defined non-LTE gases are applied, with the appropriate diagnostic techniques, to astrophysical, geophysical, and specialized

3

In other words, plasma reaction rates rather than cross sections.

This approach is taken only when direct approach fails, and then

with careful attention to the actual distributions which are averaged in the measurement.
-12-

laboratory configurations. In this way it is possible to arrive at

a physical understanding of these configurations and at the same time

to test the efficacy of the diagnostic methods.

The configurations of interest occur in a very wide range of

non-LTE states, ranging from ionized gas in interstellar space at

kinetic temperatures of only 50°K to transient discharges in the

laboratory and hot stellar atmospheres in the multimillion degree

range. For purposes of discussion, it is convenient to distinguish

four classes of configurations: the "very hot" (totally ionized)

plasma with mean kinetic energies in the range kT *~100 ev (T^-*

1, 000, 000°K), such as laboratory thermonuclear plasmas, stellar

coronas, and possibly certain explosions; the "hot" plasma,

substantially but not totally ionized, with kinetic temperatures of

the order of 1 ev < kT < 100 ev, such as in strong arc and spark

discharges, shock waves, stellar atmospheres, and certain interstellar regions; the "cool" plasma, weakly ionized with low-energy

electrons (1/20 ev < kT < a few ev), often in room temperature gases,

such as weak electric discharges, the earth's ionosphere and exosphere, and atmospheres of the cooler stars, certain flames, and

low velocity waves; the unappreciably ionized, non-LTE gas, in which

the energy transport of interest is through atomic collisions or chemical ractions. For each of these configurations, there are

three characteristics of major interest: the properties of the con- figuration as a medium for the transmission of rf radiation; its

properties in the astrophysical sense of inferring physical state

from analysis of the optical and rf radiation emitted; and its

peculiar dynamical properties due to its ionized state - the longrange interactions of the particles with each other and their

interaction with external macroscopic magnetic fields.

The first two of these properties for "hot" and "cool"

plasmas have been the subject of extensive study at the NBS

Boulder Laboratories independently and in collaboration with

the Sacremento Peak Observatory and the High Altitude Observatory.

In addition, there has been an intensive theoretical effort on the

astrophysical aspects, particularly on the theory of the solar

atmosphere. Continued at their present level, and supplemented

by the information provided in parts A and B of the program, these

efforts are nearly adequate; additional theoretical work of a modest

nature is required. Effort on the third property has been quite

small.

Only a beginning has been made in the investigation of the "very

hot" plasma. A very interesting project carried out by a group from

the Boulder Laboratories at the British Atomic Energy Laboratories

at Harwell consisted of a successful attempt to adapt a novel

millimeter wave technique (Whistler mode propagation) to the

measurement of the very high electron concentrations in a pinched

discharge in the thermonuclear device Zeta.
13-

A topical outline of the program which should be launched

follows:

1. The Plasma as an rf Medium

a. Studies of extraordinary ray propagation in magnetized

thermonuclear plasmas; em-wave boundary value problems and propagation in guided structures with plasmas as a medium; effect of

inhomogeneities that are small compared to wavelengths in static

media; propagation in turbulent and moving media.

b. Investigation of microwave propagation and microwave

boundary value experiments as a diagnostic aid; diagnostic study

of detonation and shock fronts by reflection and absorption.

c. Development of millimeter wavelength techniques as a further aid in diagnostics.

2. The Plasma as an Astrophysical and Geophysical Configuration,

Natural and Simulated

a. Theoretical and analytical interpretation of present

NBS-Sacremento Peak-High Altitude Observatory observational data on

sun, airglow, ionosphere, general stellar atmospheres, and interplanetary and interstellar media.

b. Attempts to simulate astrophysical and geophysical effects

in the laboratory by hydromagnetic coupling of atmospheric motions

with microscopic accelerations; experimental studies of simple

dynamical problems to develop analytical insight.

3. The Plasma as a Dynamical Phenomenon

a. Studies of confining fields as an aid to the production of

hot plasmas; motions of weakly and more strongly ionized gases under

magnetic fields; microscopic forces operating in plasma to distinguish the cases where hard collisions dominate from the cases where Coulomb interactions dominate.

b. Shock formation and propagation studies of exploding wires

and explosive detonations.

c. Solving aerodynamic problems of flow for wholly gaseous

mediums without a boundary, and for cases where the gas flows around

and against a solid surface.

d. Development of magnetohydrodynamic theory accompanied by

studies of trapped magnetic fields and instabilities.
-14-

IV. APPENDIX

A. Bibliography

(Selected papers during the period 1955-1959)

1. Atomic and Molecular Properties

a. Atomic Energy Levels and Spectra

Kiess, C. C. and Corliss, C. H., Description and analysis of the

first spectrum of iodine, Bur. Standards J. Res. 63A , 1 (1959).

Moore, C. E., "Vistas in Astronomy," Atomic Spectra- Their Role in

Astrophysics, Pergamon Press, London (1955).

Trees, R. E., Comparison of first, second, and third approximations in

Bacher and Goudsmit's theory of atomic spectra, J. Opt. Soc. Am.

48, 293 (1958).

Kessler, K. G., Prusch, S. B., and Stegun, I. A., Analysis of atomic

spectra with electronic digital computers, J. Opt. Soc. Am.

46, 1043 (1956).

Bozman, W. R. and Trees, R. E., Matrices of spin-orbit interaction

of the electron configuration d^s, Bur. Standards J. Res. 58,

95 (1957).

Meggers, W. F., The present experimental status of rare-earth spectra,

Optics and Spectroscopy (USSR) 6, 429 (1959).

Trees, R. E., Low even configurations in the first spectrum of

ruthenium (Ru I), Part 1, J. Opt. Soc. Am. 49, 838 (1959);

Part 2, Bur. Standards J. Res. 63A, 255 (1959).

Martin, W. C, Value of the Rydberg constant, Phys. Rev. 116 , 654

(1959).

Shenstone, A. G. and Meggers, W. F., The second spectrum of ruthenium

(Ru II), Bur. Standards J. Res. 61, 373 (1958).

Kessler, K. G., Analysis of the first spectrum of ruthenium, Bur.

Standards J. Res. 63A, 213 (1959).

Meggers, W. F., Catalan, M. A., and Sales, M., Term analysis of the

second spectrum of rhenium (Re II), Bur. Standards J. Res.

61, 441 (1958).
-15-

Russell, H. N. and Moore, C. E., The first spectrum of barium, Ba I,

Bur. Standards J. Res. 55, 299 (1955).

Meggers, W. F., Fred, M., and Tomkins, F. S., Emission spectra of

actinium, Bur. Standards J. Res. 58, 297 (1957).

Corliss, C. H. and Meggers, W. F., Improved description of hafnium

spectra, Bur. Standards J. Res. 6_1, 269 (1958).

Meggers, W. F. and Stanley, R. W., Wavelengths from thorium-halide

lamps, Bur. Standards J. Res. 61, 95 (1958).

Margoshes, M. and Scribner, B. F., The plasma jet as a spectroscopic

source, Spectrochimica Acta 138 (1959).

Moore, C. E., Atomic energy levels III (42 Mo-57 La; 72 Hf-89 Ac),

Bur. Standards Circ. 467 (1958).

Moore, C. E. and Merrill, P. W., Appendix A "Lines of the Chemical

Elements in Astrophysical Spectra," Partial Grotrian Diagrams

of Astrophysical Interest, 610,, Carnegie Institute of Washington,

Publishers (1956).

Martin, W. C, Atomic energy levels and spectra of neutral and

singly-ionized phosphorus, J. Opt. Soc. Am. 49 , 1071 (1959).

b. Molecular Spectra

Broida, H. P. and Moore, C. E., Molecules in the solar spectrum.

Mem. soc. roy. sci. Liege 18 , 217 (1957).

Harvey, K. B. and Bass, A. M., Infrared absorption of ozone and

dissociated oxygen at 4°K, J. Mol. Spectroscopy 2_, 405 (1958).

Kiess, N. H. and Broida, H. P., Spectrum of the Co molecule between

3600 A and 4200 A, Can. J. Phys. 34, 1471 (1956); Mem. soc. roy. sci. Liege 18, 544 (1957).

Moore, C. E. and Broida, H. P., Rotational lines of CH, OH, and CN

in the solar spectrum, Mem. soc. roy. sci. Liege 18 , 252 (1957).

Kiess, N. H. and Broida, H. P., Analysis of the (0.1) and (1.2) bands

of the 2

A" 2jt system of CH, Astrophys. J. 123 , 166 (1956).

Krauss, M., Electronic structure of some diatomic hydrides, J. Chem.

Phys. 28, 1021 (1958).
16-

Ransil, B. J., The electronic structure of the Ho molecule complex,

J. Chem. Phys. (1957).

Griffing, V., Jackson, J. L., and Ransil, B. J., Magnetic interaction

of H3, J. Chem. Phys. 30, 1066 (1959).

Plyler, E. K. and Tidwell, E. D., Infrared emission spectra of flames

under high resolution, Bur. Standards J. Res. 61, 263 (1958).

Allen, H. C, Jr., Plyler, E. K., and Blaine, L. R., The emission

spectrum of OH from 2.8 to 4.1u, Spectrochimica Acta j), 126

(1957).

Plyler, E. K., Tidwell, E. D., and Allen, H. C, Near infrared spectrum of nitrous oxide, J. Chem. Phys. 24, 95 (1956).

Plyler, E. K., Allen, H. C, Jr., and Tidwell, E. D., Emission

spectrum of carbon monoxide from 2.3 to 2.5 microns,

Bur. Standards J. Res. 6_1, 53 (1958).

Allen, H. C, Cross, P. C, Plyler, E. K., and Blaine. L. R., Infrared

spectrum of hydrogen sulfide from 2200-2800 cm

-

*-, J. Chem.

Phys. 24, 35 (1956).

Allen, H. C, Jr., and Plyler, E. K., Infrared spectrum of hydrogen

sulfide, J. Chem. Phys. 25, 1132 (1956).

Plyler, E. K. and Tidwell, E. D. , The precise measurement of the

infrared spectra of molecules of the atmosphere, Mem. soc. roy.

sci. Liege 18 (1957).

Stair, R., Measurement of ozone in terms of its optical absorption,

Advances in Chemistry (Series of the American Chemical Society)

21, 269 (1959).

c. Line Shapes, Intensities, and Transition Probabilities

Carrington, T., Line shape and f value in the OBrZ - ^jt transition,

J. Chem. Phys. 31, 1243 (1959).

Herman, R., Rothery, R. W., and Rubin, R. J., Line intensities in

vibration rotation bands of diatomic molecules, J. Mol.

Spectroscopy 2, 369 (1958).

Mizushima, M., Theory of the stark effect of the NO molecule, Phys.

Rev., 109, 1557 (1958).
-17-

Rohrlich, F., Theoretical multiplet strengths, Astrophys. J. 129, 441

(1959).

Kostkowski, H. J. and Bass, A. M., Slit function effects in the

direct measurement of absorption line half-widths and intensities, J. Opt. Soc. Am. 46_, 1060 (1956).

Kostkowski, H. J. and Kaplan, L. D., Absolute intensities of the

721 and 742 cm

-1 bands of C02

, J- Chem. Phys. 26, 1252 (1957).

Broida, H. P. and Carrington, T., Fluorescence and average lifetime

of excited OH ( 2Z+) in flames, J. Chem. Phys. 23, 2202 (1955).

d. Photoionization, Photodetachment

Branscomb, L. M. and Smith, S. J., Experimental cross section for

photodetachment of electrons from H~ and D", Phys. Rev. 98, 1028

(1955).

Branscomb, L. M. and Smith, S. J., Negative oxygen ions in the

upper atmosphere: The affinity and radiative attachment coefficient of atomic oxygen, Trans. Am. Geophys. Union 36 , 755 (1955).

Smith, S. J. and Branscomb, L. M., Atomic negative-ion-photodetachment

cross-section and affinity measurements, Bur. Standards J. Res.

55 (1955).

Branscomb, L. M., Smith, S. J., Burch, D. S., and Geltman, S., Photodetachment studies of negative ions, 3rd Internat. Conf. on Ionization Phenomena in Gases, Venice (1957).

Burch, D. S., Smith, S. J., and Branscomb, L. M., Photodetachment of

2

", Phys. Rev. 112, 171 (1958).

Branscomb, L. M., Burch, D. S., Smith, S. J., and Geltman, S.,

Photodetachment cross section and the electron affinity of

atomic oxygen, Phys. Rev. Ill, 504 (1958).

Geltman, S., Theory of threshold energy dependence of photodetachment

of diatomic molecular negative ions, Phys. Rev. 112, 176 (1958).

Smith, S. J. and Burch, D. S., Photodetachment cross section of the

negative hydrogen ion, Phys. Rev. Letters 2, 1645 (1959).
- 18 -

e. Negative Ion Binding Energies

Branscomb, L. M., The electron affinity of atomic oxygen, Nature 182,

248 (1958).

Branscomb, L. M. and Smith, S. J., Electron affinity of atomic oxygen,

Phys. Rev. 98, 1127 (1955).

Rohrlich, F., Atomic electron affinities, Nature 183, 244 (1959).

Johnson, H. R. and Rohrlich, F., Negative atomic ions, J. Chem.

Phys. 30,. 1068 (1959).

Branscomb, L. M., "Negative Ions," Advances in Electronics and

Electron. Physics , Academic Press, New York (1957).

Branscomb, L. M. and Smith, S. J., Electron affinity of atomic

sulfur and empirical affinities of the light elements, J.

Chem. Phys. 25, 598 (1956).

f . Collision Cross Sections

Branscomb, L. M., Calculated calibration points for negative ion

appearance potentials, J. Chem. Phys. 29, 452 (1958).

Krauss, M. and Kropf, A., Vibrational structure in the ionization

efficiency curves of hydrogen and deuterium molecules, J.

Chem. Phys. 26, 1776 (1957).

Dibeler, V. H. and Reese, R. M., Multiple ionization of sodium

vapor by electron impact, J. Chem. Phys. 31, 282 (1959).

Potter, R. F., Ion-atom interchange in air, J. Chem. Phys. 23,

2462 (1955).

Ruthberg, S., Microwave double-sweep method for analysis of timedependent cavity characteristics, Rev. Sci. Instr. 29 , 999 (1958)

Carrington, T., Rotational transfer in the fluorescence spectrum of

OH ( 2Z+), J. Chem. Phys. 31, 1418 (1959) Letter to the Editor.

Leder, L. B., Inelastic scattering of 20-kev electrons in metal

vapors, Phys. Rev. 107, 1569 (1957).

Marton, L., Schubert, D. C, and Mielczarek, S. R., Electron optical

image of an atomic beam, J. Appl. Phys. 27, 419 (1956).
-19-

2. Transport Properties and High Temperatures

a. Theory of Non-Equilibrium Rate Processes and Mechanics

Shuler, K. E. and Rubin, R. J., On the relaxation of vibrational

non-equilibrium distributions, III: The effect of radiative

transitions on the relaxation behavior, J. Chem. Phys. 26, 137

(1957).

Rubin, R. J. and Shuler, K. E., Relaxation of vibrational non- equilibrium distributions: I. Collisional relaxation of a system of harmonic oscillators, J. Chem. Phys. 25, 59 (1956);

II. The effect of the collisional transition probabilities

on the relaxation behavior, J. Chem. Phys. 25, 68 (1956);

III. The effect of radiative transitions on the relaxation

behavior, J. Chem. Phys. 26, 137 (1957).

Shuler, K. E., Studies in non-equilibrium rate processes, II: The

relaxation of vibrational non-equilibrium in distributions in

chemical reactions and shock waves, J. Phys. Chem. 61, 849 (1957),

Herman, R. and Shuler, K. E., Studies in nonequilibrium rate processes.

IV. The rotational and vibrational relaxation of a system of

rotating oscillators, J. Chem. Phys. 29, 366 (1958).

Herman, R. and Rubin, R. J., Vibrational energy exchange between

diatomic molecules and a surface, J. Chem. Phys. 29, 591 (1958).

Bazley, N. W., Montroll, E. W., Rubin, R. J., and Shuler, K. E.,

Studies in non-equilibrium rate processes. III. The vibrational

relaxation of a system of anharmonic oscillators, J. Chem.

Phys. 28, 700 (1958).

Montroll, E. W. and Shuler, K. E., "Application of the Theory of

Stochastic Processes to Chemical Kinetics," Advances in

Chemical Physics I, Interscience Publishers, New York (1959).

Shuler, K. E., On the perturbation of the vibrational equilibrium

distribution of reactant molecules by chemical reactions,

7th Internat. Symp. on Combustion, London and Oxford (1958).

Shuler, K. E., Analysis of vibrational relaxation data in shock wave

experiments, J. Chem. Phys. 30, 1631 (1959).

Shuler, K. E., Relaxation processes in multistate systems, Phys.

Fluids, 2, 442 (1959).

Shuler, K. E., On the specification of transient nonequilibrium

systems, 6th Internat. Symp. on Combustion (1957).
-20-

Oppenheim, I. and Ross, J., Temperature dependence of distribution

functions in quantum statistical mechanics, Phys. Rev. (1957).

Oppenheim, I., Statistical mechanical theory of transport processes,

Proc. Of Midwestern Conf. On Theoretical Physics (1958).

Oppenheim, I. and Mazur, P., Density expansions of distribution

functions. I. Virial expansion for finite closed systems;

canonical ensemble, Physics 23, 197 (1957); II. Density

expansions in the grand canonical ensemble, Physics 23, 216

(1957).

Shuler, K. E., On the kinetics of elementary gas phase reactions at

high temperatures, 5th Internat. Symp. on Combustion (1955).

Herman, R. and Rubin, R. J., Model for vibrational relaxation of

diatomic gases behind shock waves, Phys. Fluids 2, 547 (1959).

Mazur, J. and Rubin, R. J., Quantum mechanical calculation of the

probability of an exchange reaction for constrained linear

encounters, J. Chem. Phys. 31, 1395 (1959).

b. Chemical Kinetics, Experimental

Herron, J. T., Franklin, J. L., and Bradt, P., Mass spectrometric

study of the reactions of some hydrocarbons with active nitrogen, Can. J. Chem. 37, 579 (1959).

Herron, J. T., Franklin, J. L., Bradt, P., and Dibeler, V. H., Kinetics

of nitrogen atom recombination, J. Chem. Phys. Letters, 29, 230

(1958); J. Chem. Phys. 30, 879 (1959).

Klein, R., McNesby, J. R., Scheer, M. D., and Schoen, L. J., Kinetics

of D atom reactions with H

2

, J. Chem. Phys. 30, 58 (1959).

McKinley, J. D., Jr., and Shuler, K. E., Kinetics of the high temperature heterogeneous reaction of chlorine and nickel between

1,200 and 1,700°K, J. Chem. Phys. 28 (1958).

Ruehrwein, R. A. and Hashman, J. S., Formation of ozone from atomic

oxygen at low temperatures, J. Chem. Phys. 30 , 823 (1959).

Klein, R. and Scheer, M. D., Reaction of hydrogen atoms with solid

oxygen at 20°K, J. Chem. Phys. 31, 278 (1959).

Broida, H. P., "Spectroscopic studies of solids condensed at 4.2°K

from electric discharge through nitrogen, oxygen, hydrogen,

water, and ammonia," The Threshold of Space, Pergamon Press,

London (1957).
-21-

c. Gas Phase Chemiluminescence

Dressier, K, Absorption spectrum of vibrationally excited N2 in active

nitrogen, Letter to Editor, J. Chem. Phys. 30, 1621 (1959).

Beale, B. E., Jr., and Broida, H. P., Spectra study of a visible,

short -duration afterglow in nitrogen, J. Chem. Phys. 31, 1030

(1959).

Kurzseg, U. H: and Broida, H. P., Vibrational intensity distributions

in the nitrogen afterglow, J. Mol. Spectroscopy 3_, 388 (1959).

Kiess, N. H. and Broida, H. P., Emission spectra for mixtures of atomic

nitrogen and organic substances, 7th Symp. on Combustion,

London (1958).

Broida, H. P. and Heath, D. F., Luminous reaction between carbon

monoxide and atomic nitrogen, J. Chem. Phys. 26, 1352 (1957).

Ferguson, R. E., On the origin of the electronically excited Co

radical in hydrocarbon flames, J. Chem. Phys. 23, 2085 (1955).

McKinley, J. D., Jr., and Polyanyi, J. C, Chemiluminescence in

the system atomic sodium plus atomic hydrogen, Can. J. Chem.

36, 107 (1958).

Broida, H. P., Experimental temperature measurements in flames and

hot gases, Temperature, Its Measurement and Control in Science

and Industry 2j_ 265 (1955).

Kostkowski, H. J. and Broida, H. P., Spectra absorption method for

determining population "temperatures" in hot gases, J. Opt. Soc.

Am. 46, 246 (1956).

Kurzseg, U. H., Bass, A. M., and Broida, H. P., Spectra of afterglows

and discharges from nitrogen-oxygen mixtures, J. Mol. Spectroscopy 1, 184 (1957).

d. Spectroscopic Temperature Measurements

Carrington, T., Electronic quenching of OH (^Z+) in flames and its

significance in the interpretation of rotational rel axation,

J. Chem. Phys. 30, 1087 (1959).
-22-

Carrington, T. and Broida, H. P., Wall effects on rotational population

of 0H2z+ in a microwave discharge, J. Mol. Spectroscopy 2_, 273

(1958).

Ferguson, R. E. and Broida, H. P., Atomic flames: Spectra "temperatures"

and products, 5th Internat. Symp. on Combustion (1955).

Broida, H. P. and Heath, D. F., Spectroscopic survey of energy distributions of OH, ^2) an<* CH radicals in low-pressure acetyleneoxygen flames, J. Chem. Phys. 26, 223 (1957).

Broida, H. P. and Kostkowski, H. J., Experimental proof for the

existence of nonthermal rotational distributions of 0H( Z+) in flames, J. Chem. Phys. 25, 676 (1956).

Herzfeld, C. M., Incomplete equilibrium and temperature measurement,

J. Wash. Acad. Sci. 46, 269 (1956).

e. Thermodynamic Properties of Ionized Gas

Hilsenrath, J., Klein, M., and Sumida, D. Y., Mechanized computation

of thermodynamic tables at the NBS: The calculation of the

equilibrium composition and thermodynamic properties of dissociated and ionized gaseous system, Proc. Symp. Thermodynamic

and Transport Properties of Gases, Liquids, and Solids,

New York (1959).

Hilsenrath, J., Green, M. S., and Beckett, C. W., The internal energy

of highly ionized gases, Proc. 4th Internat. Astronautical

Congr., Amsterdam (1958).

Hilsenrath, J., Klein, M., and Woolley, H. W., Tables of thermodyanmic

properties of air including dissociation and ionization from

1500°K to 15,000°K, U.S.A.F. Report AEDC-TR-59-20, December

(1959).

Woolley, H. W., Thermodynamic properties of gases at high temperature.

I. Chemical equilibrium among molecules, atoms, and atomic ions

considered as clusters, Bur. Standards J. Res. 61, 469 (1959).

Woolley, H. W., Thermodynamic functions for atomic ions, ASTIA Document

AD 96302, April (1957).
-23-

3. Plasma Physics and Astrophysics

a. Plasma Physics

Tchen, C. M., Approximate theory on the stability of interfacial

waves between two streams, J. Appl. Phys. 27 , 1533 (1956).

Tchen, C. M., Stability of oscillations of superposed fluids, J. Appl.

Phys. 27, 760 (1956).

b. Astrophysics

Gallet, R. M., Aerodynamical mechanisms producing electronic density

fluctuations in turbulent ionized layers, Proc . Inst. Radio

Engrs. 43, 1240 (1955).

Chapman, S., Thermal diffusion in ionized gases, Proc. Phys. Soc.

(London) 72, 353 (1958).

Jefferies, J. T. and Thomas, R. N., Source function in a nonequi librium

atmosphere, II. Depth dependence of source function for

resonance and strong subordinate lines, Astrophys. J. 127, 667

(1958).

Jefferies, J. T. and Thomas, R. N., Source function in a non-equilibrium

atmosphere, III. The influence of a chromosphere, Astrophys.

J. 129 , 401 (1959).

Pottasch, S. R. and Thomas, R. N., Departures from the Saha equation

under varying conditions of Lyman continuous opacity, Astrophys.

J. 130, 941 (1959).

Kiess, C. C, Corliss, C. H., Kiess, H. K., and Corliss, E. L. R.,

High dispersion spectra of Mars, Astrophys. J. 126, 579 (1959).

Jefferies, J. and Pottasch, S., The nova outburst, III. The ionization of hydrogen gas by an exciting star, Ann. Astrophys. J.

22, 318 (1959).

Branscomb, L. M. and Pagel, B. E. J., Atomic and molecular negative

ions in stellar atmospheres, Monthly Notices Roy. Astronomical

Soc. 118, 258 (1958).

Burgers, J. M. and Thomas, R. N., Preface to Proc. 3rd Symp. on Cosmical

Gas Dynamics, Cambridge (1957); Rev. Modern Phys. 30, 908 (1958).
-24-

Pottasch, S. R., Bright rims in diffuse nebulae, Rev. Modern Phys,

30, 1053 (1958).

c. Solar Physics

Moore, C. E. and Broida, H. P., OH in the solar spectrum, Bur.

Standards J. Res. 63A, 279 (1959).

Warwick, C. S., Green coronal line intensity and geomagnetism,

J. Geophys. Res. 64, 527 (1959).

Warwick, C. S. and Wood, M. B., A study of limb flares and

associated events, Astrophys. J. 128, 801 (1959).

Tandberg -Hans sen, E., Curtis, W., and Watson, K., The emission of

Hel, X10830, during the great flare of August 26, 1958, Astrophys. J. 129, 238 (1959).

Athay, R. G. and Thomas, R. N., On the use of the early Balmer

lines to extend the photospheric model, Astrophys. J. 127,

96 (1958).

Athay, R. G. and Thomas, R. N., The chromosphere near active regions,

Astrophys. J. 125, 788 (1957).

d. Upper Atmosphere Physics - Airglow and Aurorae

Gallet, R. M., The very low-frequency emissions generated in the

earth's exosphere, Proc. Inst. Radio Engrs. 47, 211 (1959).

Gallet, R. M., The spectrum of the electron density fluctuations in

the ionosphere, Proc. Polar Atmosphere Symp., Oslo (1956).

Chapman, S. and Davies, K. , On the approximate daytime constancy

of the absorption of radio waves in the lower ionosphere, J.

Atmospheric and Terrest. Phys. 13, 86 (1958).

Thomas, J. A. and Smith, E. K., A survey of the present knowledge

of sporadic-E ionization, J. Atmospheric and Terrest. Phys.

13, 295 (1959).

Agy, V., Ionospheric effects produced by solar flare radiation,

Phys. Rev. 102, 917 (1956).

Smith, S. J., Burch, D. S., and Branscomb, L. M., Experimental

photodetachment cross section and the ionospheric detachment

rate for 0(*), Ann. Geophys. 14, 225 (1958).
-25-

e. Ionosphere

Chapman, S., The earth and its environment, Proc. Inst. Radio Engrs.

47, 137 (1959).

Gates, D. M., Atmospheric research, Americana Annual, p. 62 (1958).

Chapman, S., The aurora in middle and low latitudes, Nature 179, 7 (1957).

Hunten, D. M., Roach, F. E., and Chamberlain, J. W., A photometric

unit for the airglow and aurora, J. Atmospheric and Terrest.

Phys. 8j_ 345 (1956).

Chamberlain, J. W., Oxygen red lines in the airglow. I. Twilight

and night excitation processes, Astrophys. J. 127, 54 (1958),

Roach, F. E., The night airglow, Proc. Inst. Radio Engrs. 47, 267 (1959).

Roach, F. E., Tandberg -Hans sen, E., and Megill, L. R., Movements

of airglow cells, J. Atmospheric and Terrest. Phys. 13, 122

(1958).

Brandt, J. C. and Chamberlain, J. W., Interplanetary gas. I.

Hydrogen radiation in the night sky, Astrophys. J. 130, 670

(1959).
-26-

B. PARTIAL LIST OF PARTICIPANTS

There follows a partial list of scientists engaged in activities

described in this note, with indications of their research fields

and organizational location within the National Bureau of Standards.

The latter may be helpful in making contact with individuals for

the purpose of obtaining reprints or further technical information.

ALLEN, Harry, C, Jr. : Ph.D., University of Washington (Seattle), 1951;

theory of molecular structure; Atomic Physics Division, Radiometry

Section (at Cambridge University, Cambridge, England, through September,

1960).

BASS, Arnold M. : Ph.D., Duke University, 1949; spectroscopy with

emphasis on the spectra of molecules in solids at low temperature,

and on the use of spectroscopic methods in high temperature measurement; Heat Division, Chief, Free Radicals Section.

BEATY, Earl C. : Ph.D., Washington University, 1956; atomic mobilities

and optical pumping, atomic clocks; Atomic Physics Division, Atomic

Physics Section.

BECKETT, Charles W. : Ph.D., University of California, 1945; dynamic

and transfer properties and related structural properties of matter

throughout the temperature range from ordinary temperatures up to

millions of degrees; Assistant Chief, Heat Division.

BRANSCOMB, Lewis M. : Ph.D., Harvard University, 1949; ionic physics

and atomic collision phenomena, upper atmosphere physics; Chief,

Atomic Physics Division.

BROIDA, Herbert P. : Ph.D., Harvard University, 1949; molecular

spectroscopy, chemical physics, spectra of condensed radicals;

Heat Division, Free Radicals Section (at University of Cambridge,

Cambridge, England, through December, 1960).

BROWN, Lawrence M. : Ph.D. candidate, Catholic University; equation

of state of gases, shock waves, exploding wire phenomena, compilation

of properties of isotopic hydrogen compounds, review of isotope

effects on chemical reaction rates; Heat Division, Equation of State

Section.

CARRINGTON , Tuc ker : Ph.D., California Institute of Technology, 1952;

spectroscopic study of molecular collisions; Heat Division, Molecular

Kinetics Section.
-27-

COOPER, J. W.

Theoretical physics; photoionization cross sections;

Office of the Director.

CORLISS, Charles H. : Spectrochemical analysis, description of

atomic spectra, measurement of spectral intensity, development of

spectroscopic light sources; Atomic Physics Division, Spectroscopy

Section.

DIBELER, Vernon H. : Ph.D., Columbia University, 1950; application

of mass spectrometry to molecular physics, electron impact phenomena

in molecular gases; Atomic Physics Division, Mass Spectrometry Section.

FANO, U. : Dr. Sc, University Torino, Italy, 1929-34; theoretical

physics, scattering theory, radiation transfer through materials;

Office of the Director, Consultant.

GELTMAN, Sydney : Ph.D., Yale University, 1952; theory of ionic

mobilities, atomic scattering, ionization, and photodetachment;

Atomic Physics Division, Atomic Physics Section.

GREEN, Melville S. : Ph.D., Princeton, 1951; statistical mechanics

of time -dependent phenomena, quantum statistical mechanics of manybody systems; equilibrium transport properties at high temperatures;

Heat Division, Chief, Statistical Physics Section.

HERRON, John T. : Ph.D., McGill University, 1957; appearance potentials

of positive and negative ions in halogen molecules; Atomic Physics

Division, Mass Spectrometry Section.

HERZFELD, Charles M. : Ph.D., University of Chicago, 1951; solid

state physics, trapped radicals, theory of spectra of atoms and

solids, group theory; Chief, Heat Division.

HILSENRATH, Joseph : Thermodynamic properties of gases, liquids,

and solids, high pressure thermodynamics, equation of state of

highly ionized gases; Heat Division, Chief, Equation of State Section.

JACKSON, J. L. : Ph.D., New York University, 1950; application of

statistical methods to various fields of physics, in particular - plasmas, trapped radicals, irreversible statistical mechanics,

crystallization of polymers, and electrical noise; Heat Division,

Statistical Physics Section.

KESSLER, Karl G. : Ph.D., University of Michigan, 1947; atomic

spectra, wavelength standards of length; Atomic Physics Division,

Chief, Spectroscopy Section.
-28-

KLEIN, M. : Ph.D. candidate, University of Maryland; transport and

equilibrium properties of gases; Heat Division, Statistical Physics

Section.

KOSTKOWSKI, Henry J .: Ph.D., Johns Hopkins University, 1954; infrared

spectroscopy, temperatures of flames, optical pyrometry, plasma

thermometry; Heat Division, Temperature Physics Section.

KRAUSS, Morris : Ph.D., University of Utah, 1955; molecular orbitals,

mass spectra; Chemistry Division, Thermochemistry Section.

MARTIN, William C : Ph.D., Princeton, 1956; atomic spectra; Atomic

Physics Division, Spectroscopy Section.

MARTON, L. : Ph.D., University of Zurich, 1924; electron optics,

inter ferome try, electron scattering in solids and gases; Atomic

Physics Division, Chief, Electron Physics Section.

McKINLEY, John P., Jr. : Ph.D., New York University, 1953; kinetics

of heterogeneous reactions; Heat Division, Molecular Kinetics Section.

MEIJER, Paul H. E. : Ph.D., Leyden University, 1950; theoretical

physics, statistical mechanics, and quantum theory; Consultant,

Heat Division (part-time at Catholic University).

MENDLOWITZ, Harold : Ph.D., University of Michigan, 1954;

characteristic electron energy losses in solids, electron optics,

electron-nuclear scattering, plasmas in solids, electron polarization, oscillator strengths, optical properties of solids, atomic

scattering; Atomic Physics Division, Electron Physics Section.

MOHLER, Fred L. : Ph.D., Johns Hopkins University, 1917; atomic

physics, ionization potentials, physics of the cesium positive

column plasma, mass spectrometry; Atomic Physics Division, Chief,

Mass Spectrometry Section.

NICHOLLS, Ralph W. : Ph.D., University of London, 1951; experimental

and theoretical laboratory studies on molecular spectra of astrophysical, aeronomical, combustion, and radiation chemical interest;

Heat Division (temporarily on leave of absence for the academic

year 1959-60 from the University of Western Ontario).

OPPENHEIM, I. : Ph.D., Yale University, 1952; fundamentals of

statistical mechanics and the statistical mechanics of fluids and

plasmas, transport processes; Heat Division, Statistical Mechanics

Section (at Convair, San Diego, through December, 1960).
29-

FICCIRELLI, R. A. ; Ph.D., Catholic University, 1956; statistical

mechanics, evaluation of the quantum partition function, generalization of the Boltzmann equation to higher densities and to include

inhomogeneities, derivation of a kinetic equation for plasmas which

includes all collision effects; Heat Division, Statistical Physic

Section.,

PLYLER, Earle K. : Ph.D., Cornell University, 1924; infrared emission

and absorption spectra; Atomic Physics Division, Chief, Radiometry

Section.

REESE, Robert M. ; Measuring excitation functions of multiply

charged ions near the threshold; Atomic Physics Division, Mass

Spectrometry Section.

ert J^; Ph.D., Cornell University, 1951; plastic wave

propagation in materials exhibiting strain-rate effects, vibrational

relaxation and its influence on relative line intensities of diatomic

molecules, chemical exchange reaction probabilities, models for

Brownian motion; Heat Division, Temperature Physics Section.

SCHEER, Milton D. : Ph.D., New York University, 1951; kinetics of

surface ionization and low temperature chemistry; Heat Division,

Molecular Kinetics Section.

SCHUBAUER, Galen B. ; Ph.D., Johns Hopkins University, 1934; aero- dynamics, hydrodynamics, and hydraulics, specific field - turbulence

and boundary layer research; Mechanics Division, Chief, Fluid

Mechanics Section.

SHULER, Kurt E. : Ph.D., Catholic University, 1949; theoretical

chemical physics, energy transfer in inelastic collisions, relaxation

phenomena, non-equilibrium statistical mechanics; Consultant to

the Chief, Heat Division.

SHUMAKER, John B .

y Jr.; Ph.D., Yale University, 1952; spectroscopic

measurements in arc plasmas; Heat Division, Temperature Physics

Section.

SIMPSON, J. Arol ; Ph.D., Lehigh University, 1953; characteristic

energy losses, electron spectroscopy^ Atomic Physics Division,

Electron Physics Section.

SITTERLY, Charlotte M. : Ph.D., University of California, 1931;

compilation of atomic energy levels, preparation of multiplet

tables, study of atomic spectra, identification of solar lines;

Atomic Physics Division, Spectroscopy Section.
-30-

SMITH, Stephen J, ; Ph.D., Harvard University, 1954; photodetachment

of negative ions; electron-atom interaction; Atomic Physics Division,

Chief, Atomic Physics Section.

TCHEN, Chan Mou; Dr. of Tech. Sci, Technical University, Delft,

1947; hydrodynamics, stochastic processes, theoretical plasma

physics; Applied Mathematics Division, Mathematical Physics Section.

THOMPSON, R. : Experimental plasma physics; Heat Division, Equation

of State Section.

TREES, Richard E. : Ph.D., University of Pennsylvania, 1951; atomic

energy levels; Atomic Physics Division, Spectroscopy Section.

TSAI, P. : Sc.D., Massachusetts Institute of Technology, 1952;

aircraft pneumatics, high temperature pvt measurement; Heat

Division, Equation of State Section.

WIESE, Wolfgang L. : Ph.D., University of Kiel, Germany, 1957;

plasma physics, atomic transition probabilities; Atomic Physics

Division, Spectroscopy Section.

WOOLLEY. H. W. : . Ph.D., University of Michigan, 1955; thermodynamic

properties of hydrogen isotopes, ortho-para effects, ideal gas

properties, gas imperfection effects, third virial coefficient,

equations of state, thermodynamic functions for atoms and atomic

ions at high temperature, equilibrium properties of gases at high

temperatures; Heat Division, Statistical Physics Section.

ZWANZIG, R. : Ph.D., California Institute of Technology, 1952;

statistical mechanics; Heat Division, Statistical Physics Section.

ZALUBAS, R. ; Ph.D., Georgetown University, 1955; description and

analysis of atomic spectra; Atomic Physics Division, Spectroscopy

Section.

Participants in the Boulder Laboratories:

BAILEY, D. K. : Ionospheric physics, scatter propagation, physics

of the lower ionosphere and cosmis rays; Radio Propagation Physics

Division (Boulder).

GALLET, R. M. : Certificates in philosophy, physics, and mathematics,

University of Sorbonne, 1942-43; theory of the exosphere, plasma

physics, radio astronomy; Radio Propagation Physics Division, Chief,

Upper Atmosphere Research Section (Boulder)..
-31-

GATES, D. : Ph.D., University of Michigan, 1948; infrared spectroscopy

of the upper atmosphere; Assistant Chief, Radio Propagation Physics

Division (Boulder).

POWERS, R. S. : Candidate for Ph.D., University of Wisconsin; scattering theory and transport properties of gases; Gaseous Physics Group

(Boulder).

RICHARDSON, J. M. : Ph.D., Harvard University, 1951; microwave standards, microwave spectroscopy of O2 with application to atomic

frequency standards, millimeter wave measurements and interferometry,

plasma physics with regard to the interaction of microwave radiation

with plasmas; Chief, Gaseous Physics Group (Boulder).

ROACH, F . E: Ph.D., University of Chicago, 1934; upper atmosphere

physics, physics of the airglow; Radio Propagation Physics Division,

Chief, Airglow and Aurora Section.

ROHRLICH, F. : Ph.D., Harvard University, 1948; elementary particles,

quantum electrodynamics, scattering theory, theory of atomic spectra;

Consultant, Director's Office. (Boulder).

THOMAS, R. N. : Ph.D., Harvard University, 1948; theory of stellar

atmospheres and radiation transfer in hot gases, gas dynamics;

Consultant, Director's Office (Boulder).

VanZANDT, T. : Ph.D., Yale University, 1954; upper atmosphere theory,

physics of the F2 layer; Radio Propagation Physics Division, SunEarth Relationships Section (Boulder).

WACKER, P. S. ; Ph.D., Catholic University, 1954; microwave spectroscopy and molecular structure; Consultant^ Radio Standards

Laboratory. (Boulder).

WARWICK, C : Ph.D., Radcliffe, 1952; solar physics and related

ionospheric physics; Radio Propagation Physics Division, Sun-Earth

Relationships Section (Boulder).

USCOKK-DC

U.S. DEPARTMENT OF COMMERCE

Frederick H. Mueller, Secretary NATIONAL BUREAU OF STANDARDS

A. V. Aslin, Director THE NATIONAL BUREAU OF STANDARDS

The scope of activities of the National Bureau of Standards at its major laboratories in Washington, D.C., and

Boulder, Colorado, is suggested in the following listing of the divisions and sections engaged in technical work.

In general, each section carries out specialized research, development, and engineering in the field indicated by

its title. A brief description of the activities, and of the resultant publications, appears on the inside of the front cover. WASHINGTON, D.C.

Electricity and Electronics. Resistance and Reactance. Electron Devices. Electrical Instruments. Magnetic Measurements. Dielectrics. Engineering Electronics. Electronic Instrumentation. Electrochemistry.

Optics and Metrology. Photometry and Colorimetry. Photographic Technology. Length. Engineering

Metrology.

Heat. Temperature Physics. Thermodynamics. Cryogenic Physics. Rheology. Molecular Kinetics. Free

Radicals Research. Atomic and Radiation Physics. Spectroscopy. Radiometry. Mass Spectrometry. Solid State Physics. Electron Physics. Atomic Physics. Neutron Physics. 'Radiation Theory. Radioactivity. X-rays. High

Energy Radiation. Nucleonic Instrumentation. Radiological Equipment.

Chemistry. Organic Coatings. Surface Chemistry. Organic Chemistry. Analytical Chemistry. Inorganic

Chemistry. Electrodeposition. Molecular Structure and Properties of Gases. Physical Chemistry. Thermochemistry. Spectrochemistry. Pure Substances.

Mechanics. Sound. Mechanical Instruments. Fluid Mechanics. Engineering Mechanics. Mass and Scale. Capacity, Density, and Fluid Meters. Combustion Controls.

Organic and Fibrous Materials. Rubber. Textiles. Paper. Leather. Testing and Specifications. Poly- mer Structure. Plastics. Dental Research.

Metallurgy. Thermal Metallurgy. Chemical Metallurgy. Mechanical Metallurgy. Corrosion. Metal

Physics.

Mineral Products. Engineering Ceramics. Glass. Refractories. Enameled Metals. Constitution and Microstructure.

Building Technology. Structural Engineering. Fire Protection. Air Conditioning, Heating, and Refrigeration. Floor, Roof, and Wall Coverings. Codes and Safety Standards. Heat Transfer. Concreting Materials.

Applied Mathematics. Numerical Analysis. Computation. Statistical Engineering. Mathematical Physics.

Data Processing Systems. SEAC Engineering Group. Components and Techniques. Digital Circuitry.

Digital Systems. Analog Systems. Application Engineering.

• Office of Basic Instrumentation. • Office of Weights and Measures. BOULDER, COLORADO

Cryogenic Engineering. Cryogenic Equipment. Cryogenic Processes. Properties of Materials. Gas Liquefaction. Radio Propagation Physics. Upper Atmosphere Research. Ionospheric Research. Regular Propagation

Services. Sun-Earth Relationships. VHF Research. Radio Warning Services. Airglow and Aurora. Radio

Astronomy and Arctic Propagation.

Radio Propagation Engineering. Data Reduction Instrumentation. Modulation Research. Radio Noise. Tropospheric Measurements. Tropospheric Analysis. Propagation Obstacles Engineering. Radio-Meteorology. Lower Atmosphere Physics.

Radio Standards. High Frequency Electrical Standards. Radio Broadcast Service. High Frequency Impedance Standards. Electronic Calibration Center. Microwave Physics. Microwave Circuit Standards. Radio Communication and Systems. Low Frequency and Very Low Frequency Research. High Fre- quency and Very High Frequency Research. Ultra High Frequency and Super High Frequency Research. Modulation Research. Antenna Research-. Navigation Systems. Systems Analysis. Field Operations.