Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 1
PREPUBLICATION COPY—SUBJECT TO FURTHER EDITORIAL CORRECTION
177
178 Preface and Acknowledgments
179
180 In the fall of 2010, the Office of the U.S. Department of Energy’s (DOE’s) Under
181 Secretary for Science asked for a National Research Council (NRC) committee to investigate the
182 prospects for generating power using inertial confinement fusion (ICF) concepts, acknowledging
183 that a key test of viability for this concept—ignition1—could be demonstrated at the National
184 Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) in the relatively near
185 term. The committee was asked to provide an unclassified report. However, DOE indicated that
186 to fully assess this topic, the committee’s deliberations would have to be informed by the results
187 of some classified experiments and information, particularly in the area of ICF targets and
188 nonproliferation. Thus, the Panel on the Assessment of Inertial Confinement Fusion Targets
189 (“the panel”) was assembled, composed of experts able to access the needed information (for
190 member biographies, see Appendix A). The panel was charged with advising the Committee on
191 the Prospects for Inertial Confinement Fusion Energy Systems on these issues, both by internal
192 discussion and by this unclassified report. The statement of task for the panel is given in Box P.1.
193
Box P.1 Statement of Task for the Panel on the Assessment of Inertial Confinement Fusion Targets
A Panel on Fusion Target Physics (“the panel”) will serve as a technical resource to the
Committee on Inertial Confinement Energy Systems (“the Committee”) and will prepare a report
that describes the R&D challenges to providing suitable targets, on the basis of parameters
established and provided to the Panel by the Committee.
The Panel on Fusion Target Physics will prepare a report that will assess the current
performance of fusion targets associated with various ICF concepts in order to understand:
1. The spectrum output;
2. The illumination geometry;
3. The high-gain geometry; and
4. The robustness of the target design.
The panel will also address the potential impacts of the use and development of current
concepts for Inertial Fusion Energy on the proliferation of nuclear weapons information and
technology, as appropriate. The Panel will examine technology options, but will not provide
recommendations specific to any currently operating or proposed ICF facility.
194
195 The panel interpreted the terms used in its statement of task in the following way.
196 “Illumination geometry” not only is interpreted to mean the physical arrangement and timing of
197 laser or particle beams incident on the target but also is generalized to mean “delivering driver
198 energy to the target.” In this way, the magnetic forces in pulsed-power schemes are also
199 included. “High-gain geometry” is interpreted as designs that enable the energy incident on the
200 target to be converted efficiently into fuel burn and high yield.2 “Spectrum output” is interpreted
201 to include all of the types of emissions (photons, ions, neutrons, and debris) from the fusion
202 target and their energy spectra. Depending on the type of reaction chamber used (solid wall,
1
The operative definition of ignition adopted by the panel, “gain greater than unity,” is the same as that used in the
earlier National Research Council NRC report: Review of the Department of Energy's Inertial Confinement Fusion
Program,Washington, D.C.: National Academy Press (1997).
2
High yield is defined broadly as much more than 10 times the fusion energy produced as driver energy delivered to
the target.
1
OCR for page 2
PREPUBLICATION COPY—SUBJECT TO FURTHER EDITORIAL CORRECTION
203 wetted wall, liquid wall, gas-filled, evacuated, and so on) these emissions may or may not reach
204 the chamber wall; however, a detailed discussion of the effects on the wall is beyond the scope of
205 this report. “Robustness of the target design” is interpreted in two ways: (1) the inherent
206 “physics robustness,” which relates to the performance margins of the design being large enough
207 compared to the physics uncertainties that reliable performance can be assured under ideal
208 conditions, and (2) “engineering robustness,” which relates to the target’s ability to deliver
209 reliable performance even under nonideal conditions such as variations in driver energy, target
210 manufacturing defects, errors in target positioning, or driver beam misalignment.
211 This unclassified report contains all of the panel’s conclusions and recommendations. In
212 some cases, additional support and documentation required the discussion of classified material,
213 which appears in classified appendixes in a separate version of this report. ICF is an active
214 research field, and scientific understanding continues to evolve. The information discussed here
215 is accurate as of the date presented to the panel (see Appendix B), though in some cases more
216 recent updates are included; if so, this is noted in the text.
217 This report was reviewed in draft form by individuals chosen for their diverse
218 perspectives and technical expertise in accordance with procedures approved by the National
219 Research Council’s Report Review Committee. The purpose of this independent review is to
220 provide candid and critical comments that will assist the institution in making its published
221 report as sound as possible and to ensure that the report meets institutional standards for
222 objectivity, evidence, and responsiveness to the study charge. The review comments and draft
223 manuscript remain confidential to protect the integrity of the process.
224 We wish to thank the following individuals for their review of this report:
225
226 Bedros Afeyan, Polymath Research Inc.,
227 Roger Bangerter, E.O. Lawrence Berkeley National Laboratory (retired),
228 Michael Corradini, University of Wisconsin,
229 Jill Dahlburg, Naval Research Laboratory,
230 Richard Garwin, IBM Thomas J. Watson Research Center,
231 David Hammer, Cornell University,
232 Frank von Hippel, Princeton University,
233 Arjun Makhijani, Institute for Energy and Environmental Research,
234 David Overskei, Decision Factors Inc.,
235 Robert Rosner, University of Chicago, and
236 Douglas Wilson, Los Alamos National Laboratory.
237
238 Although the reviewers listed above have provided many constructive comments and
239 suggestions, they were not asked to endorse the conclusions or recommendations, nor did they
240 see the final draft of the report before its release. The review of this report was overseen by
241 Louis J. Lanzerotti, New Jersey Institute of Technology. Appointed by the NRC, he was
242 responsible for making certain that an independent examination of this report was carried out in
243 accordance with institutional procedures and that all review comments were carefully
244 considered. Responsibility for the final content of this report rests entirely with the authoring
245 committee and the institution.
246
2
OCR for page 3
PREPUBLICATION COPY—SUBJECT TO FURTHER EDITORIAL CORRECTION
247 The panel also thanks the NRC staff for its dedicated work, in particular Sarah Case, who
248 got the panel started off on the correct path, and Greg Eyring, who persevered in getting both the
249 classified and the unclassified reports over many hurdles.
250
251 John F. Ahearne, Chair
252 Panel on Assessment of Inertial Confinement Fusion Targets
3
