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both to astronomy and to the missions of the Department of
Energy and other agencies. These laboratories can make
unique contributions to the studies of many astrophysics
problems, especially by satellite observations; by the
study of properties of matter at high temperatures and
densities; and by large-scale numerical calculations
involving hydrodynamics, nuclear reactions, and energy
transport. Access by astronomers to the powerful com-
puters at the DOE laboratories has been a particularly
unique and valuable resource.
DOE needs scientists with astrophysics backgrounds in
many aspects of energy research, and these scientists are
helped to retain their originality and versatility by par-
ticipation in fundamental research activities. There is
a strong synergism between the physics of many terrestrial
energy problems and the situations encountered in astro-
nomical environments, and theoretical astrophysicists are
often uniquely qualified to make important contributions
to energy research as a result of their broad training in
gas dynamics, plasma physics, atomic processes, and
radiative-transfer theory. We recommend a continuing
effort to strengthen the ties between the DOE institu-
tions and the astrophysics community. Involving their
staff more directly in astronomical research will enhance
their awareness of areas where they can make special con-
tributions; similarly, an awareness by university faculty
of the capabilities of the government laboratories can
lead to productive research collaborations.
III. LABORATORY ASTROPHYSICS
We take laboratory astrophysics to be theoretical and
experimental physics and chemistry that relates directly
to the interpretation of astronomical observations and
that enters into astronomical theories of the phenomena
involved. It includes atomic, molecular, and solid-state
physics, together with chemistry, nuclear physics, elemen-
tary-particle physics, plasma physics, condensed-matter
physics, and fluid mechanics.
A. Atomic and Molecular Physics and Chemistry
Because spectroscopy has been the main measurement tech-
nique used by astronomers to derive the element abun-
dances, temperatures, densities, and motions of astro-
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nomical objects, atomic physics has long been an integral
part of astronomical research. With the discovery of
astrophysical molecules, molecular physics has assumed a
similar significance. The accuracy with which the physi-
cal conditions can be inferred from the spectroscopic
observations depends directly on the precision and breadth
of the data base of atomic and molecular processes. Atom-
ic and molecular processes are more than diagnostic probes
of the physical environment. They are often critical in
the determination of the evolution of the astronomical
object in question.
Recent advances in our capability to carry out spectro-
scopic observations at high resolution in the radio, sub-
millimeter, infrared, ultraviolet, x-ray, and gamma-ray
regions of the electromagnetic spectrum (in addition to
the optical region) offer unprecedented opportunities for
the detailed study of the physical conditions of such
varied environments as those of the dark interstellar
clouds where star formation is in progress; the outer
envelopes of stars (with associated stellar winds and
mass loss); novae and supernovae; the accretion flow onto
white dwarfs, neutron stars, and black holes in binary
systems; and the nuclei of active galaxies and quasars.
The development of astronomical spectroscopy over the
extended wavelength range now used in astronomy makes new
demands on atomic and molecular data, and the extraordi-
nary range of physical conditions makes new demands on
our quantitative understanding of atomic and molecular
processes.
Technological progress in experimental atomic and
molecular physics and chemistry has been extremely rapid,
and the potential for substantial improvements in mea-
surement accuracy and for extensions to new kinds of
experiments is considerable. Many, though not all, of
the advances have stemmed from the development of tunable
lasers, which will soon cover the range from the far
infrared through to the ultraviolet regions, with an
emerging possibility for the construction of lasers
operating at x-ray wavelengths. Important developments
have occurred in the production of controlled beams of
neutral and highly ionized atomic particles and in the
use of synchrotron sources of ultraviolet and x-ray
photons. Of particular significance to astronomy are
advances in submillimeter spectroscopy, which have opened
to astronomical study the wavelength region in which most
of the power emitted by interstellar clouds may appear.
The ability of laser techniques to prepare and to moni-
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tor very-short-lived species heralds new applications of
laboratory astrophysics. AS one example, resonance-
ionization spectroscopy allows the detection of single
atoms and introduces the possibility of studying extremely
reactive transient species and of measuring the rate coef-
ficients of very slow processes, which are still important
on astronomical time scales.
The techniques for the production of slowly moving
beams will permit the measurement of cross sections for
collision processes at the low temperatures occurring in
molecular clouds and will provide a vital ingredient of
theoretical models of molecular formation and the
associated cooling processes.
In planetary science, the need is urgent for spectro-
scopic information about a lengthy list of molecular
species. Line intensities, pressure shifts, broadening
coefficients, and line shapes at pressures and tempera-
tures and in gas mixtures relevant to planetary atmo-
sphere environments are required. Obtaining such data is
not easy and will require the provision and maintenance
of highly sophisticated experimental and theoretical
programs with a strong astronomical interest.
In the study of stellar atmospheres, and of the solar
atmosphere, there is a rapidly growing need for accurate
atomic and molecular data. The sophistication of the
theory of stellar atmospheres greatly exceeds the quality
of the atomic and molecular data that enter into the
theory. Particularly noteworthy was the provision of new
oscillator strengths for iron, which led to an increase
by an order of magnitude in the derived iron abundance in
the Sun. The influence of solar opacities on the pre-
dicted neutrino flux is an important unsettled question
today. Detailed theory of redistribution for the forma-
tion of hydrogen Lyman and Balmer lines is especially
needed for the solar atmosphere.
The past decade has seen a marked deterioration in
laboratory facilities for basic spectroscopic studies,
which, if not reversed, will have dismal consequences for
astronomy. m e advance of astronomical spectroscopy into
the vacuum ultraviolet region places unprecedented demands
on our knowledge of atomic and molecular spectroscopy.
Many ultraviolet lines have been observed with the Inter-
national Ultraviolet Explorer that may be critical diag-
nostics but remain unidentified. To realize the scien-
tific potential of the ultraviolet spectroscopic capabil-
ity of the Space Telescope will require a renewed effort
in laboratory spectroscopy.
. . . _ ~
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In x-ray astronomy, the interpretation of spectral data
will place new demands on laboratory astrophysics. Accu-
rate values of transition probabilities and collisional
excitation rates of highly stripped systems are needed.
More accurate collisional ionization rates are needed for
the proper interpretation of x-ray emission spectra. For
example, in supernova remnants the departures from ioniza-
tion equilibrium are likely to have important consequences
for abundance determination. Charge-transfer processes
require elucidation, and the effects of the secondary
emissions that they generate must be explored. Auger
ionization and dielectronic recombination processes in
highly ionized systems and the fluorescent responses need
to be delineated. Similar data are required in the study
of fusion plasmas such as those produced with Alcator and
Tokomak devices, and a close coordination between x-ray
diagnosis of fusion plasmas and the study of x-ray sources
in astronomy would be mutually beneficial. Accelerator-
based experiments have been very productive in providing
data on highly stripped systems and should be continued.
The infrared and submillimeter spectroscopy of the
interstellar medium in our own and in external galaxies
offers exciting possibilities. Shocks in dense inter-
stellar clouds lead to emission in the rotation-
vibrational levels of molecular hydrogen. The excitation
cross sections for rotation-vibration transitions are
critical parameters in the interpretation of the infrared
observations. m e mechanism of collisional dissociation
in astrophysical shocks is still highly uncertain. Other
emissions from ionized and neutral carbon and from carbon
monoxide appear in the submillimeter region, and their
interpretation involves the excitation cross sections by
collisions with atomic and molecular hydrogen.
In interstellar clouds, schemes have been advanced for
the gas-phase formation of interstellar molecules. Part
of their success may be due to inadequacies and uncertain-
ties in the rates of the postulated chemical processes.
We hope to progress sufficiently so that the distribution
in the galaxy of isotopic forms such as D and 13C could
be obtained reliably from observations of interstellar
molecules. Accurate molecular data would transform inter-
stellar chemistry from a qualitatively attractive descrip-
tion of possibilities to quantitative diagnostic procedure
and would lead to a realistic description of the role of
chemical processes in cloud collapse and star formation.
Rapid progress in laboratory and theoretical studies
is technically possible on many fronts. To achieve it
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will require sophisticated and expensive instrumentation
supported by extensive general laboratory facilities.
Theoretical analyses should augment all measurement
programs.
Basic theoretical procedures for the calculation of
atomic and molecular properties have advanced substan-
tially in the past decade, and many critical questions of
laboratory astrophysics can be answered reliably. m e
necessary research will usually involve large amounts of
fast computer time supported by experienced research
groups with a diversity of theoretical and computational
expertise. Such groups can be created and maintained
only with the provision of a secure funding basis.
The interplay between theory and experiment in atomic
and molecular physics has long been a mutually productive
one. Because of the vast range of physical conditions
encountered in astronomical research it is particularly
important to maintain their interaction in research in
laboratory astrophysics.
Recent studies have suggested that the discipline of
atomic and molecular physics has been seriously under-
funded over many years, so much so that the future lia-
bility of atomic and molecular physics research in the
United States is brought into question. If the pattern
of funding persists, it could affect most severely those
areas of greatest relevance to astronomy.
B. Nuclear Physics
Nuclear physics has been a basic aspect of astrophysics
because of the importance of nuclear processes in stars
The diminishing research into low-energy nuclear processes
in this country is viewed with concern by the astrophysi-
cal community, which wishes to incorporate low-energy
laboratory data of higher quality into the construction
of more accurate models of stars in all stages of
evolution.
There are five areas to which we wish to draw special
attention, areas that we expect greatly to affect astro-
physics in the coming decade: the solar neutrino ques-
tion, stellar nucleosynthesis, supernova theory, cosmic-
ray isotopic composition, and nuclear chronology.
The solar neutrino problem remains one of the most per
plexing in astrophysics, apparently striking at the very
roots of our understanding of stars and stellar evolution.
An important result of the last decade is the failure by
.
-
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Davis to detect solar neutrinos at a level predicted by
theory. Recent laboratory results on an important cross
section [the 3He(alpha, gamma)7 Be reaction] and new
calculations for solar opacities have led to large dif-
ferences (in opposite directions) for the predicted neu-
trino flux, and it still remains on the order of three
times the measured upper limit. It is of very high impor-
tance to re-examine carefully all the relevant cross sec-
tions and atomic-physics data that go into the nuclear
reactions and stellar models. With the new high-current
accelerators, sensitive detectors, improved atomic models,
and appropriate computer support, this is all possible
and should have the highest priority. It is important
also to continue the development of techniques that show
promise of measuring the flux and spectra of the neutrinos
from the primary proton-proton reaction of solar energy
generation. The flux and spectra of these neutrinos are
model-independent, and their measurement will lead to a
crucial test of the fundamental idea of hydrogen burning
in main-sequence stars.
Stellar nucleosynthesis research is expected to take a
new and qualitatively different turn in the coming decade
because of the large increases in computer capability.
Instead of the idealized, parameterized models of the
past, calculations can be carried out in specific astro-
physical contexts, for specific stars of specific com-
position. Necessary for these techniques to make sense
are not only large computers but accurate reaction rates
and realistic stellar-evolution models. This program
should yield testable predictions for differences in
nucleosynthetic products from stars of different metal-
licity, a reliable framework for interpretation of astro-
nomical abundance data, and information on the production
of short-lived nuclei that may carry important evidence
on the formation of the solar system and may produce
decays that are observable from satellites such as the
Gamma Ray Observatory. These calculations will provide a
framework for constructing accurate chemical evolutionary
models for the Galaxy, including constraints on the behav-
ior of past stellar populations. Also emerging from these
studies should be an understanding of the puzzling iso-
topic anomalies now being found in primitive solar-system
material.
Predictions for the return of the products of nucleo-
synthesis to the interstellar medium will be more reliable
with accurate nuclear reaction data derived from labora-
tory cross-section measurements over the entire range of
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nuclear species. Similarly, a better knowledge of nuclear
physics and many-body techniques is needed to generate
accurate equations of state at or near nuclear density.
A proper understanding of the supernova phenomenon may
require accurate two-dimensional models of collapse, in
which the effects of rotation, nonlocal convection, and
magnetic fields are included. Use of the best computer
technology is necessary for these developments, and much
work at the conceptual level remains to be done.
Studies of cosmic-ray isotopic composition are expected
to advance significantly in the next decade if the satel-
liteborne experiments now planned are launched. Isotopic
ratios carry a wealth of information about the abundances
and nucleosynthetic history of the material at the source
much less ambiguously than do elemental abundances. Num-
bers of recent experiments have revealed isotopic ratios
that differ significantly from the solar-terrestrial ones,
and future work promises to be very exciting. Questions
that may be answered include the old one of whether the
cosmic rays are accelerated from the material of the
interstellar medium or from fresh supernova ejecta. If
the latter, what sort of supernova? If the former, or
conceivably even if the latter, what is the metallicity
and overall abundance pattern of the region from which
the comic rays come? Abundances of the light elements,
together with laboratory data on spallation, should
permit a correct interpretation of the results for the
· ~
heavier species.
The great hope for nuclear chronology in the coming
decade may be understanding the potentially extremely
powerful Re-Os chronometer, which may be understood with
(1) more accurate information about the relevant neutron-
capture cross section; (2) a more precise measurement of
the 187Re half-life; and (3) an improved analysis of
the abundances and geochemical effects for Re and Os.
The u-m chronometer may also be improved through the
inclusion of more sophisticated nuclear physics and
better reprocess models.
Laboratory investigations relevant to nuclear astro-
physics are supported generally by the Nuclear Science
Divisions of the National Science Foundation and of the
Department of Energy. The arrangements have worked satis-
factorily, and the support has been effective. There is
a continuing need to encourage experimental and theoret-
ical studies of the nuclear processes occurring in astro-
physical environments, and it should be recognized by the
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agencies that nuclear astrophysics is a discipline that
merits strong support.
C. Elementary-Particle Physics
Cosmology and the astrophysics of cataclysmic events such
as supernovae and quasars involve matter at extremely
high temperature and density. These exciting areas of
modern astronomy stand to benefit by the continued sup-
port of elementary-particle physics using high-energy
accelerators both with stationary targets and colliding
beams. There is a crucial need to know about the true
nature of baryon/lepton conservation, about the masses
and other properties of the vector bosons that mediate
the universal weak interaction, about the possibility of
neutrino exchange and the determination of neutrino
masses, and about the reality and implications of quark
confinement.
The nature of the nucleon-nucleon interaction, deter-
mined through collisions of relativistic baryons, is vital
to our understanding of the origin and structure of neu-
tron stars and of the formation of black holes.
Astronomical observations may provide useful con-
straints on elementary-particle theories. The limits on
the observed cosmic deceleration place restrictions on
the sum of all neutrino masses, and the observed helium
abundance limits the total number of neutrino flavors
permitted within the framework of big-bang cosmology.
Phase transitions may have occurred in the early
Universe in which the electroweak gauge symmetry and the
strong interaction chiral symmetry were successively
broken. A possible consequence of the phase transitions
is the development of dynamical perturbations leading
eventually to the density perturbations from which are
formed the gravitationally bound structures now present
in the Universe. Since these structures provide evidence
on the form and spectra of the perturbations, there is an
exciting potential link between the interactions in the
very early Universe and the macroscopic structure of the
Universe today.
The Department of Energy holds elementary-particle and
high-energy physics as a national trust. Astronomy ac-
knowledges this trust in part because of its contribution
to fundamental knowledge but also because of its critical
applications to astrophysical circumstances involving
extremes of density and temperature.
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D. Solid-State Physics and Chemistry
The physics and chemistry of the solid state is poten-
tially of great significance to astronomy, and many
experiments that address critical astrophysical questions
can be carried out in the laboratory. For example, inter-
stellar grains play a basic role in star formation. Their
surfaces are locations for the formation of molecules, and
by absorbing destructive ultraviolet radiation, the grains
permit molecules to survive. Photoelectric emission from
grains is a substantial heat source for the interstellar
gas. The grains may be the source of the diffuse inter-
stellar absorption lines, and the formation and destruc-
tion of grains is an important sequence in the return of
material to the interstellar gas.
It has become clear that the solar system contains iso-
topically heterogeneous materials from different stellar
sources. Some of these sources appear to have injected
freshly synthesized materials formed immediately before
the solar system formed. This injected material contains
short-lived radioactive nuclei and stable nuclei that can
be used to establish the state of the interstellar medium
from which the solar nebula separated. The discovery of
isotopic heterogeneities and of extinct short-lived radio-
active elements in the solar system has opened new
approaches to solar-system formation. mese observations
also yield insight into the particular nuclear astrophysi-
cal processes within supernovae, in the isotopic and chem-
ical state of supernova debris and interstellar matter.
Given reliable laboratory data on primitive solar-system
materials (meteorites and comets), it becomes possible to
explore the early stages of condensation in the solar
nebula. This field should expand and become a major field
of activity for the next decade, involving nuclear phys-
ics, astrophysics, and cosmochemistry. Because it is now
possible to analyze directly in the laboratory aggregates
from the early solar nebula, interplanetary dust grains,
and partially preserved pre-solar-system materials, a
major shift in the experimental approaches will occur.
Experimental activities should be expanded to include the
study of these exotic materials, using sophisticated
equipment and techniques that allow the study of grains
composed of 101°-lOll atoms. Extended efforts will
be needed to study the morphology, chemistry, and iso-
topic composition of interplanetary dust grains and
cometary material. Experiments to investigate the
mechanism of grain condensation and formation under
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conditions simulating the solar nebula and stellar atmo-
spheres should be encouraged in order to develop our
understanding of the different types of stellar debris in
the dust and gas phases of the interstellar medium and
their chemical interactions during aggregation. Labora-
tory investigations should provide sufficient clues to
permit the development of realistic models of the forma-
tion of the solar system and star formation generally.
Data are also needed on the optical properties of
solids, especially at infrared and ultraviolet wave-
lengths. They are required to aid in understanding the
reflectance characteristics of the surfaces of the Gali-
lean satellites and the asteroids in order to infer their
mineralogical types, as well as for the study of the rings
around Saturn and Uranus. The structure of planetary
interiors and the behavior of volatiles depend on equa-
tions of state, phase changes, solubility, vapor pres-
sures, condensation, and nucleation properties of a wide
range of materials over a wide range of pressures and
temperatures.
An important step in the next decade will be the growth
of a multidisciplinary scientific community actively work-
ing to understand the detailed state of the interstellar
medium and the mechanism of accumulation of matter to
form stars and planetary systems.
E. The Physics of Condensed Matter
The behavior of matter under extreme conditions of den-
sity, temperature, magnetic, and gravitational fields is
one of the frontier problems in physics. It is not only
a challenging problem in itself, but it is also central
to our understanding of pulsars, compact x-ray sources
(accreting neutron stars, black holes, and white dwarfs),
a gravitational collapse, and the early Universe. During
the past decade, extended temporal and broadband spectro-
scopic studies carried out by x-ray astronomical satel-
lites have led to the identification of specific compact
x-ray sources as accreting neutron stars, black holes, or
white dwarfs in close binary systems. Such sources pro-
vide a unique opportunity to study matter under extreme
conditions not accessible in the terrestrial laboratory.
Quantitative theoretical models of neutron stars have
been developed that demonstrate that detailed studies of
pulsars and pulsating x-ray sources will lead to a greatly
increased understanding of dense and superdense hadron
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matter, hadron superfluidity, high-temperature plasma in
superstrong magnetic fields, and the possible existence
of pion condensates, neutron solids, or quark liquids in
their cores.
We may expect significant progress in the coming
decade in our understanding of the equation of state of
cold neutron matter at densities greater than that of
nuclear matter, which determines the mass-radius rela-
tion, crustal extent, and maximum mass of neutron stars.
We need a better understanding of neutron and proton
superfluidity and its relation to the glitch behavior in
pulsars and of new phases of matter at very high den-
sities, including a condensed Bose pion fluid and/or a
phase transition to a quark liquid. An understanding of
the equation of state of hot (about 10 meV) high-density
matter, which determines the behavior of collapsing cores,
is probably crucial for the proper description of the
supernova phenomenon and the production of supernova rem-
nants. The behavior of condensed matter in superstrong
magnetic fields may well determine the behavior of the
pulsar phenomenon through its influence on the conduc-
tivity and effective work function of the neutron star
surface.
High-energy observational astronomy will continue to
provide an arena for the interaction of the physics of
condensed matter and astrophysics to the benefit of both.
F. Plasma Physics
The discipline of plasma physics had its origin in astron-
omy, and it continues to play a fundamental role in the
interpretation of almost all astronomical phenomena.
Among the many critical areas of direct relevance to
astrophysics are magnetic-field reconnection, the inter-
action of magnetic fields with turbulence, the nonlinear
growth of plasma instabilities, the nature of collision-
less shocks, the interaction of magnetic fields with
plasma motions, and particle-transport processes.
Laboratory investigations of plasma processes can make
substantial contributions to research into astrophysical
plamas. The extraordinary complexity of the phenomena
has obscured the connections and communication between
those active in laboratory research and those in astro-
physical research. We believe it is most valuable in the
next decade to create closer relationships by which the
intrinsic synergism between laboratory and astrophysical
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plasma research can be reinforced. Theoretical and
experimental studies of the interplanetary medium should
be especially productive in joining the interests of the
two communities of plama physicists
.
The Department of Energy supports research on fusion
plamas and on magnetohydrodynamic plasmas. In astronomi-
cal environments, energy generation appears often to be a
result of as yet poorly understood plama processes whose
study may be particularly rewarding in the exploration of
new energy sources.
G. Fluid Mechanics
An understanding of fluid mechanics is vital to astro-
physics. Progress in astrophysics will continue to
demand use of the concepts and techniques of modern
fluid dynamics.
In modern fluid dynamics the computer provides a
vitally important laboratory. The use of carefully posed
numerical experiments has been a powerful tool for under-
standing the subtle phenomena prevalent in this field.
In astrophysics these techniques have been used to model
astronomical situations, but the level of usage has often
fallen short of that required to understand properly the
processes involved.
Increased availability of computing power will lead to
substantial expansion in nonlinear modeling and in numer-
ical experimentation. An effective strategy for astro-
physical fluid dynamics and magnetohydrodynamics is the
development of numerical techniques that are to be tested
by comparison with critical laboratory experiments and
analytic solutions and then used to extrapolate to other-
wise inaccessible astrophysical conditions.
Particularly amenable to such techniques are problems
related to turbulence, for which classical mixing-length
approaches are not adequate. The energy flux carried by
convection, convective overshoot, hydromagnetic dynamos,
and turbulence in radiation-pressure dominated fluids are
all areas in which considerable progress is expected.
Related areas in which considerable emphasis is being
placed in fluid dynamics are studies of intermittence and
of nonlinear waves, both of which have immediate applica-
bility to astrophysics, through the physics of accretion
disks, jets, chromospheres and coronas, and the origin of
spiral structure. Progress should occur in the descrip-
tion of two-phase flows (such as stars and gas in gal-
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axles, dust and gas for protostars, radiation and gas in
hot stars and the young Universe, and neutrinos and had-
rons in gravitational collapse). The study of the dynam-
ics of "chemical" waves in astrophysics, for example in
the interstellar medium and in oscillating nuclear reac-
tions in convective stars, is just beginning. Several
basic gaps in our understanding of the evolution of stars
are related to hydrodynamic flow in otherwise static
objects, specifically, the effects of rotation, mixing,
and mass loss.
The fluid dynamics of jets is ripe for experimental
and numerical study, which may elucidate processes fun-
damental to the understanding of jets in Galactic binar-
ies, radio galaxies, and quasars. Continued experimental
studies of the properties of rotating superfluids are
important to an understanding of neutron-star interiors.
Other aspects of fluid dynamics are the coupling of con-
vection and pulsation for application to variable stars,
the interaction of fluid dynamics and spectral radiation
for application to theory of spectral lines, the theory
of drops and bubbles for application to the formation of
dust through the liquid drop phase, and the dynamics of
fluids with large molecular weights to allow simulations
of small scale heights in the laboratory. The experimen-
tal studies of convection will be particularly valuable.
The problems of astrophysics demand an increasing
knowledge of detailed aspects of fluid-dynamical processes
and their relation to the other physical processes that
are occurring. In order to make progress in understand-
ing these complex phenomena, state-of-the-art techniques
and resources should be made available to astrophysicists.
Thus, there is a general need for increased support of
experimental and theoretical research into astrophysical
fluid mechanics.
H. Recommendations for Laboratory Astrophysics
RECOMMENDATION III. 1: The National Aeronautics and Space
Administration should establish, as part of its mission
planning, the support for research in the basic physics
and chemistry that is needed for the interpretation of
astronomical observations from space and for the develop-
ment of quantitative theories of astrophysical phenomena.
We have already pointed out the reasons why NASA
should support research in theoretical astrophysics.
Equally compelling are the arguments for support of
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laboratory astrophysics: without the understanding of the
nature of the physical processes underlying the astronomi-
cal phenomena observed in space missions and without the
base of data on those physical processes, the interpreta-
tion of the observations is surely tentative and may be
misleading in the design of future missions. In many
cases, a relatively modest expenditure for laboratory
studies is the most effective way for NASA to ensure that
a given space mission will yield a better understanding
of the cosmos. NASA should recognize its larger responsi-
bilities to the sciences that its missions help to illumi-
nate and create a program of research in better balance
with its essential objectives.
RECOMMENDATION III.2: Because laboratory astrophysical
processes are common to a wide range of energy-related
researches, the Department of Energy should continue to
recognize laboratory astrophysics as an appropriate area
for funding support.
The Department of Energy is concerned with the dis-
covery, development, and efficient utilization of energy
resources. No other science offers insight into such a
range of potential energy sources as does astronomy. No
other science is concerned with such a range of physical
environments as is astronomy. Laboratory astrophysics,
responding to the demands of astronomy, embraces a broad
extent of research that encompasses many of the perceived
needs of energy-related research but also enlarges the
potential for innovative discoveries. m e Department of
Energy appears in practice to have recognized this close
relationship, which is mutually beneficial.
RECOMMENDATION III.3: The National Science Foundation's
(NSF) Astronomy Division should seek to augment existing
research programs in basic physics to ensure that labora-
tory astrophysics is included as a strong component of
these activities. In addition, the NSF Physics Division
should continue support of its programs in laboratory
astrophysics.
There are many programs of research in basic physics
that are supported by various agencies for diverse pur-
poses. There already exist experimental apparatus and
techniques, together with theoretical and computational
skills, that could effectively address problems of astro-
physical interest if these research programs could be
moved in that direction. Selective augmentation of such
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300
funding, so that astrophysical demands could be met as
part of these research programs, is to be encouraged.
Relatively modest expenditures could lead to a substan-
tial return in the provision of the basic data of labora-
tory astrophysics and in encouraging a continuing inter-
est by researchers whose motivation is largely stimulated
by other areas of scientific activity.
RECOMMENDATION III.4: Subject to periodic review, long-
term support should be provided to strengthen existing
centers to ensure that laboratory astrophysics is a major
influential part of the research.
Laboratory astrophysical research is necessarily con-
ducted on a long time scale. In periods of restricted
funding, it is particularly important that existing cen-
ters with a record of distinguished contributions be main-
tained and strengthened. Support over a longer term must
be secured; otherwise the research will inevitably respond
to the demands of mission-oriented agencies with immediate
problems, and a pattern develops that inhibits the
approach to deep and difficult questions that can be
answered only by careful and lengthy examination. In
laboratory astrophysics we draw attention in particular
to the critical role of the National Bureau of Standards
(NBS) in supporting laboratory spectroscopy. This pro-
gram, which has a long record of productivity, is rele-
vant to a broad range of national research needs includ-
ing astrophysics. We also urge continued support by NBS
for the compilation of atomic energy levels. We urge
renewed and vigorous support by NBS of laboratory astro-
physics. Astronomers demand and contribute to the devel-
opment of a broad base of knowledge of fundamental atomic
and molecular processes that is the proper concern of this
agency. We more generally urge a new examination by fed-
eral agencies of their responsibilities for the long-term
health of the national research enterprise.
RECOMMENDATION III.5: Funding agencies should encourage
the convening of workshops attended by astronomers and by
laboratory astrophysicists to ensure that astronomical
needs are recognized
.
The effective implementation of our other recommenda-
tions requires mechanisms for improved communication among
astronomers, physicists, and chemists. Therefore, we
encourage workshops in which these scientists may meet in
close interaction. Workshops provide an economical means
of information exchange where new opportunities can be
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identified and different disciplines can associate in th
development of innovative approaches to common problems.
RECOMMENDATION III.6: A number of visiting fellowships
e
should be created to encourage astronomers and laboratory
astrophysicists to visit institutions where research
relevant to astronomy can be pursued.
As a supplement to Recommendation 5, we encourage the
creation of visiting fellowships, established on a regu-
lar basis, so that laboratory astrophysicists and astrono-
mers may join institutions that maintain facilities for
the support of research activities of interest to astron-
omy. The program at the Joint Institute for Laboratory
Astrophysics has been a notable success. It should be
strengthened and adopted as a model for a number of other
institutions where laboratory astrophysics and astronomy
can be pursued jointly.
RECOMMENDATION III.7: Support should be maintained for
data centers to provide critical compilations and
assessments of the basic physical data required in
quantitative applications.
Easy access to data is ultimately as important as its
acquisition. Data centers can play an important role by
providing access to data and also by providing an expert
assessment of the accuracy of the data. By emphasizing
quality, data centers can set new standards of measure-
ment and of calculation. As in other areas in which
physics and chemistry is applied to the understanding of
physical phenomena, data centers are important to
astronomy.
Representative terms from entire chapter:
interstellar medium
