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high energy density phenomena. The realization of the importance of magnetized plasmas in interstellar
and intergalactic space has generated a need for basic information on the behavior of such plasmas, often
in physical regimes far from those currently being studied for their application to magnetic fusion
reactors. Laboratory measurements will allow us to understand the formation of molecules in interstellar
space and stellar atmospheres, both critical for star formation studies, for example by studying the
complex chemical reactions on the surface of dust grains. DOE’s high energy density facilities 24 will be
able to host laboratory astrophysics experiments relevant to outstanding questions in radiative
hydrodynamics, equation of state measurements relevant to planetary interiors, and turbulent flow. They
are also performing experiments important to high energy astrophysics, specifically involving the
behavior of hot plasmas and dynamical magnetic field configurations.
The Science Frontier Panel reports call out specific needs for research in laboratory astrophysics
in order to accomplish the proposed research objectives for the next decade. New capabilities require
expanded laboratory astrophysics research in the x-ray, UV, mm & sub-mm, and IR regimes as missions
such as Herschel, JWST, and ALMA go forward. These reports highlight the need for tabulation of
spectral features for ions, molecules, and clusters of atoms. Additionally, measurements of gas phase
cross sections, for example of the polycyclic aromatic hydrocarbon molecules found in star forming
regions, are needed to understand the absorption features seen in the spectra of Galactic objects. A better
understanding of dust and ice absorption spectra and the chemistry of molecule formation is also needed.
The Funding Challenge
NSF PHY support for laboratory astrophysics has declined to about one-third of the level of two
decades ago. Although there has been an increase in the number of NSF AST laboratory astrophysics
awards in atomic and molecular physics, the combined PHY plus AST laboratory astrophysics support
has fallen to about half of what it was 20 years ago.
Short-term funding for laboratory astrophysics, for example that tied to observing cycles, is
inadequate for the health of stable laboratory astrophysics programs, and some source of stable base
funding is needed to support experimental facilities. National Laboratories may be the most dependable
long-term reservoir of capability, as most of these topics are no longer central to the interests of basic
physics at universities. The work of compiling the data into useful catalogs and databases is probably still
best done by astronomers, and it is vital to maintain databases of important astrophysical results. This
might be done at national labs or at major data centers, but needs to be coordinated among all
investigators.
CONCLUSION: DOE national laboratories, including those funded by the Office of Science
and the National Nuclear Security Administration, have many unique facilities that can
provide basic astrophysical data.
In summary, the increased need for laboratory astrophysics, due to new and highly capable
observing modes, and the relevance to other physics and engineering problems, requires a systematic,
long-term, and robust funding strategy in order to ensure successful scientific returns from missions and
programs. Support requires people, instrumentation, and maintenance of databases. AST support has been
increasing, but at far from a sufficient rate to compensate for the loss of input from the atomic physics
community and the increased needs of modern astronomical observations.
24 Such as Z and ZR (Sandia National Lab.), Omega (U. of Rochester Lab for Laser Energetics), and the
National Ignition Facility (Lawrence Livermore National Lab) and the Princeton Plasma Physics Laboratory.
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