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Laboratory Astrophysics and the State of Astronomy and Astrophysics
Laboratory astrophysics and complementary theoretical calculations are the
foundations of astronomy and astrophysics and will remain so into the
foreseeable future. The impact of laboratory astrophysics ranges from the
scientific conception stage for ground-based, airborne, and space-based
observatories, all the way through to the scientific return of these projects
and missions. It is our understanding of the under-lying physical processes and
the measurements of critical physical parameters that allows us to address
fundamental questions in astronomy and astrophysics. In this regard, laboratory
astrophysics is much like detector and instrument development at NASA, NSF, and
DOE. These efforts are necessary for the success of astronomical research being
funded by the agencies. Without concomitant efforts in all three directions
(observational facilities, detector/instrument development, and laboratory
astrophysics) the future progress of astronomy and astrophysics is imperiled.
In addition, new developments in experimental technologies have allowed
laboratory studies to take on a new role as some questions which previously
could only be studied theoretically can now be addressed directly in the lab.
With this in mind we, the members of the AAS Working Group on Laboratory
Astrophysics, have prepared this State of the Profession Position Paper on the
laboratory astrophysics infrastructure needed to ensure the advancement of
astronomy and astrophysics in the next decade.Comment: Position paper submitted by the AAS Working Group on Laboratory
Astrophysics (WGLA) to the State of the Profession (Facilities, Funding and
Programs Study Group) of the Astronomy and Astrophysics Decadal Survey
(Astro2010
Nuclear Astrophysics
Nuclear physics has a long and productive history of application to
astrophysics which continues today. Advances in the accuracy and breadth of
astrophysical data and theory drive the need for better experimental and
theoretical understanding of the underlying nuclear physics. This paper will
review some of the scenarios where nuclear physics plays an important role,
including Big Bang Nucleosynthesis, neutrino production by our sun,
nucleosynthesis in novae, the creation of elements heavier than iron, and
neutron stars. Big-bang nucleosynthesis is concerned with the formation of
elements with A <= 7 in the early Universe; the primary nuclear physics inputs
required are few-nucleon reaction cross sections. The nucleosynthesis of
heavier elements involves a variety of proton-, alpha-, neutron-, and
photon-induced reactions, coupled with radioactive decay. The advent of
radioactive ion beam facilities has opened an important new avenue for studying
these processes, as many involve radioactive species. Nuclear physics also
plays an important role in neutron stars: both the nuclear equation of state
and cooling processes involving neutrino emission play a very important role.
Recent developments and also the interplay between nuclear physics and
astrophysics will be highlighted.Comment: To be published in the Proceedings of 19th Lake Louise Winter
Institute (15-21 February 2004). 9 pages, 3 figure
Astrophysics
Historical account of astrophysics development based on photometry and spectroscop
Nuclear Astrophysics
Nuclear astrophysics is that branch of astrophysics which helps understanding
some of the many facets of the Universe through the knowledge of the microcosm
of the atomic nucleus. In the last decades much advance has been made in
nuclear astrophysics thanks to the sometimes spectacular progress in the
modelling of the structure and evolution of the stars, in the quality and
diversity of the astronomical observations, as well as in the experimental and
theoretical understanding of the atomic nucleus and of its spontaneous or
induced transformations. Developments in other sub-fields of physics and
chemistry have also contributed to that advance. Many long-standing problems
remain to be solved, however, and the theoretical understanding of a large
variety of observational facts needs to be put on safer grounds. In addition,
new questions are continuously emerging, and new facts endanger old ideas. This
review shows that astrophysics has been, and still is, highly demanding to
nuclear physics in both its experimental and theoretical components. On top of
the fact that large varieties of nuclei have to be dealt with, these nuclei are
immersed in highly unusual environments which may have a significant impact on
their static properties, the diversity of their transmutation modes, and on the
probabilities of these modes. In order to have a chance of solving some of the
problems nuclear astrophysics is facing, the astrophysicists and nuclear
physicists are obviously bound to put their competence in common, and have
sometimes to benefit from the help of other fields of physics, like particle
physics, plasma physics or solid-state physics.Comment: LaTeX2e with iopart.cls, 84 pages, 19 figures (graphicx package), 374
updated references. Published in Reports on Progress in Physics, vol.62, pp.
395-464 (1999
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