scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Advanced Diagnostics for Magnetic and Inertial Fusion

01 Jan 2002-Plasma Physics and Controlled Fusion (IOP Publishing)-Vol. 45, Iss: 2, pp 182-182
TL;DR: In this article, a collection of papers, written by specialists in the field, on advanced topics of nuclear fusion diagnostics is presented, focusing on the requirements imposed by the physical issues to be studied.
Abstract: This book is a collection of papers, written by specialists in the field, on advanced topics of nuclear fusion diagnostics. The 78 contributions were originally presented at the International Conference on Advanced Diagnostics for Magnetic and Inertial Fusion held at Villa Monastero, Italy in September 2001. Both magnetically confined and inertial fusion programmes are quite extensively covered, with more emphasis given to the former scheme. In the case of magnetic confinement, since the present international programme is strongly focused on next-step devices, particular attention is devoted to techniques and technologies viable in an environment with strong neutron fluxes. Indeed, in the first section, the various methods are considered in the perspective of performing the measurements of the relevant parameters in conditions approaching a burning plasma, mainly in the Tokamak configuration. The most demanding requirements, like the implications of the use of tritium and radiation resistance, are reviewed and the most challenging open issues, which require further research and development, are also clearly mentioned. The following three sections are devoted to some of the most recent developments in plasma diagnostics, which are grouped according to the following classification: `Neutron and particle diagnostics', `Optical and x-ray diagnostics' and `Interferometry, Polarimetry and Thomson Scattering'. In these chapters, several of the most recent results are given, covering measurements taken on the most advanced experiments around the world. Here the developments described deal more with the requirements imposed by the physical issues to be studied. They are therefore more focused on the approaches adopted to increase the spatial and time resolution of the diagnostics, on some methods to improve the characterisation of the turbulence and on fast particles. Good coverage is given to neutron diagnostics, which are assuming increasing relevance as the plasma parameters approach ignition. Spectroscopic systems and their recent developments are well represented, whereas edge diagnostics are somewhat thin on the ground. A dedicated section is devoted to the latest tests on radiation effects and technological issues. The problems of damage to optical components and the difficulties presented by the determination of the tritium inventory are described. In the last part, the new diagnostic systems of the most recent experiments (under construction or recently operated) are reported. Various aspects of some diagnostics not included in the three previous sections are also covered, with particular emphasis on microwaves and infrared diagnostics. The book is well suited for specialists and, more generally, for people involved in nuclear fusion, who need information about the most recent developments in the field of plasma diagnostics. The papers cover many aspects of the challenges and possible solutions for performing measurements in fusion machines approaching reactor conditions. On the other hand, the contributions are in general quite advanced and would be challenging for people without a significant background in plasma diagnostics and nuclear fusion. The quality of the paper is more than satisfactory both from the point of view of clarity and of graphics. Moreover, at the beginning of the book, several papers make a considerable effort to put diagnostic issues in the wider context of present day nuclear fusion research. For those topics, which are too involved to be completely described in a conference contribution, in general adequate references are provided for deeper investigation. A Murari Approximately one third of the papers included in this volume deal with diagnostics related to inertial confinement fusion plasmas (i.e., laser-produced plasmas and pulsed-power). These papers discuss recent developments in charged particle diagnostics, neutron diagnostics, optical and x-ray measurements along with laser and particle probing diagnostics. The resulting collection of papers is comprehensive and wide-ranging and all of the major laboratories in Europe, the US, and Japan are represented. There is important discussion on the development of diagnostics for the National Ignition Facility, LMJ, and future ultra-high intensity laser experiments as well as papers on wire array z-pinch experiments. It is especially useful to have the contributions from inertial confinement fusion experiments intermingled with those from magnetic confinement fusion. The separation between these two approaches to fusion is often unfortunately large, so one of the pleasing things about this book is that it is very easy for readers familiar with experimental research in one area to compare `state of the art' plasma diagnostics in the other area. Hopefully this will facilitate the development of new ideas in both areas. This book is a conference proceedings and as such, almost all of the papers included are quite brief and are highly technical. Consequently, the book is not particularly pedagogical and would be most useful to researchers already working in this area of physics. For these readers, however, Advanced Diagnostics for Magnetic and Inertial Confinement Fusion is an excellent overview of the present status of fusion plasma diagnostics. K Krushelnick
Citations
More filters
Journal ArticleDOI
TL;DR: In this paper, the authors describe the requirements for high reliability in the systems (diagnostics) that provide the measurements in the ITER environment, which is similar to those made on the present-day large tokamaks while the specification of the measurements will be more stringent.
Abstract: In order to support the operation of ITER and the planned experimental programme an extensive set of plasma and first wall measurements will be required. The number and type of required measurements will be similar to those made on the present-day large tokamaks while the specification of the measurements—time and spatial resolutions, etc—will in some cases be more stringent. Many of the measurements will be used in the real time control of the plasma driving a requirement for very high reliability in the systems (diagnostics) that provide the measurements. The implementation of diagnostic systems on ITER is a substantial challenge. Because of the harsh environment (high levels of neutron and gamma fluxes, neutron heating, particle bombardment) diagnostic system selection and design has to cope with a range of phenomena not previously encountered in diagnostic design. Extensive design and R&D is needed to prepare the systems. In some cases the environmental difficulties are so severe that new diagnostic techniques are required. a Author to whom any correspondence should be addressed.

309 citations


Additional excerpts

  • ...field, similar to the one developed for C-MOD [216]....

    [...]

  • ...Two suitable designs have been identified, one based on a tetrode ionization gauge (‘ASDEX gauge’) [215] and the second a miniature Penning gauge using the machine field, similar to the one developed for C-MOD [216]....

    [...]

Journal ArticleDOI
01 Nov 2005
TL;DR: In this article, the technological challenges associated with preparing and installing diagnostic systems on ITER are summarized and the solutions that have been developed to overcome them are described, areas where further developments are needed are highlighted.
Abstract: The technological challenges associated with preparing and installing diagnostic systems on ITER are summarized and the solutions that have been developed to overcome them are described. Areas where further developments are needed are highlighted.

85 citations

Journal ArticleDOI
TL;DR: In this article, a concept for the absolute calibration of neutron diagnostic systems is proposed, and the development, testing in existing experiments and the engineering integration of all Neutron diagnostic systems into ITER are in progress.
Abstract: Due to the high neutron yield and the large plasma size many ITER plasma parameters such as fusion power, power density, ion temperature, fast ion energy and their spatial distributions in the plasma core can be measured well by various neutron diagnostics. Neutron diagnostic systems under consideration and development for ITER include radial and vertical neutron cameras (RNC and VNC), internal and external neutron flux monitors (NFMs), neutron activation systems and neutron spectrometers. The two-dimensional neutron source strength and spectral measurements can be provided by the combined RNC and VNC. The NFMs need to meet the ITER requirement of time-resolved measurements of the neutron source strength and can provide the signals necessary for real-time control of the ITER fusion power. Compact and high throughput neutron spectrometers are under development. A concept for the absolute calibration of neutron diagnostic systems is proposed. The development, testing in existing experiments and the engineering integration of all neutron diagnostic systems into ITER are in progress and the main results are presented.

60 citations


Cites methods from "Advanced Diagnostics for Magnetic a..."

  • ...Dynamic range for 1 ms time window Life time Housing Neutron Detector ∅ × l (cm3) Sensitivity (cm2 neutrons−1) For maximum flux 5 × 109 neutrons cm−2 s−1 camera Stilbene / NE-213 compact ∅5 × 40 10−3–1 10 (digital spectrometer ? RNC ext spectrometer [19, 20] for 100 ms time window) /monitor [27] 100 (digital monitor) Natural diamond detector ∅1 × 2 2 × 10−5 for 20 (for 100 ms 104 full power RNC ext (NDD) [18]—compact single NDD time window) seconds RNC int, VNC spectrometer NDD—flux monitor ∅1 × 2 10−3 for single NDD 50 2 × 106 full power RNC ext [18, 28] seconds RNC int, VNC 2n × 10−3 for n 100 × n ∼106 full power NDD+radiator seconds CVD diamond detector [29] ∅3 × 3 2 × 10−2 for detector 1000 2 × 106 full power RNC ext ∅25 × 0....

    [...]

Journal ArticleDOI
TL;DR: Zimmerman and Kruer as mentioned in this paper used time-resolved x-ray images to determine the motion of the radiating shock that heats the hohlraum as it propagates toward the HLSN axis, and measured the radius of radiation-driven capsules as they implode.
Abstract: Z-pinch dynamic hohlraums are a promising indirect-drive inertial confinement fusion approach Comparison of multiple experimental methods with integrated Z-pinch∕hohlraum∕capsule computer simulations builds understanding of the hohlraum interior conditions Time-resolved x-ray images determine the motion of the radiating shock that heats the hohlraum as it propagates toward the hohlraum axis The images also measure the radius of radiation-driven capsules as they implode Dynamic hohlraum LASNEX [G Zimmerman and W Kruer, Comments Plasma Phys Control Fusion 2, 85 (1975)] simulations are found to overpredict the shock velocity by ∼20–40%, but simulated capsule implosion trajectories agree reasonably well with the data Measurements of the capsule implosion core conditions using time- and space-resolved Ar tracer x-ray spectroscopy and the fusion neutron yield provide additional tests of the integrated hohlraum-implosion system understanding The neutron yield in the highest performing CH capsule implos

59 citations

Journal ArticleDOI
TL;DR: The paper makes a review of the research performed worldwide on plasma diagnostics and discusses the state of the art and the future priorities to be set.

56 citations


Cites background from "Advanced Diagnostics for Magnetic a..."

  • ...Practically all diagnostics systems [4] share, in one way or another, the use of ceramics....

    [...]