Laser fusion reactor

New fusion applications include the concept of production of intense negative ion beams ( ) (for neutral beam injection for heating and diagnostics in tokamaks or other magnetically confined plasmas (26, 28)) by using photodissociation to ion pairs (e.g. NaLi + hVyy Na + Li") in supersonic molecular beams. Another promising concept is the use of laser induced fluorescence to monitor very low tritium concentrations (as little as 10 Tj/cm ) under fusion reactor conditions (29). 

The OMEGA laser at the University of Rochester, Rochester, New York, uses a glass laser and can deliver 2,400 joules at a wavelength of 350 nanometers. OMEGA has generated 2 xio" fusion neutrons for a reaction efficiency of about 0.001%. This efficiency is far below the 25% to 75% needed for a fusion reactor. 

Menon, M. M., and A. Slotwinski, 2004, Novel Doppler Laser Radar for Diagnostics in Fusion Reactors, Review of Scientific Instruments, 75,4100-4102. 

Carbon film, which is chemically inert, can be applied as protective coating and antireflection layers for optical components for the infrared range and laser devices, wear protection, dielectric materials, coatings on fusion reactor walls, etc. Superlattices of a-C H and a-Si H have been obtained, and compound layers of a mixture of carbon and silicon have been grown. 

The extremely high peak power densities available ia particle beams and lasers can heat the small amounts of matter ia the fuel capsules to the temperatures required for fusion. In order to attain such temperatures, however, the mass of the fuel capsules must be kept quite low. As a result, the capsules are quite small. Typical dimensions are less than 1 mm. Fuel capsules ia reactors could be larger (up to 1 cm) because of the iacreased driver energies available. 

With respect to the operation of thermonuclear reactors, laser-induced fusion and heavy-ion-induced fusion are also discussed. In these concepts compression of T or D-T mixtures to high density and heating to high temperatures are achieved by irradiation with a laser beam of very high intensity or with a beam of high-energy heavy ions. 

Deuterium, either mixed with tritium or in the form of Li deuteride, LiD, is an essential ingredient in the fuel proposed for fusion power reactors. In the magnetically confined type of fusion power system, the working substance is a plasma mixture of fully ionized deuterium and tritium. In the laser or electron beam imploded type of system, the fuel form is a small sphere containing deuterium and tritium or LiD. Although power systems of these types have not yet been proved feasible, their successful development would create a market for deuterium and Li as great as the current market for eruiched uranium. 

The plasma must also have a high density for a sufficient time to permit the fusion reaction to occur. Laser heating of frozen deuterium-tritium pellets confined in a magnetic field is a method that has been tested. The neutrons formed react with lithium in an outer mantle, a reaction in which new tritium is formed. This reactor type is called Tokamak and is used in research projects in the USA and England. Similar reactors are used in France, Russia and Japan. 

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