168:, especially for photographing explosions, or less commonly for use in high altitude test vehicles. The photography of explosions and shock waves is made easy by the fact that the detonation of the argon flash lamp charge can be accurately timed relative to the test specimen explosion and the light intensity can overpower the light generated by the explosion itself. The formation of shock waves during explosions of
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as the explosion itself, depending on the construction of the lamp, between 0.1 and 100 microseconds. The duration is dependent on the length of the shockwave path through the gas, which is proportional to the length of the tube; it was shown that each centimeter of the path of shock wave through the argon medium is equivalent to 2 microseconds.
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The amount of explosive can control the intensity of the shock wave and therefore of the flash. The intensity of the flash can be increased and its duration decreased by reflecting the shock wave by a suitable obstacle; a foil or a curved glass can be used. The duration of the flash is about as long
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of the gas has to be compressed to sufficient temperature. The light intensity rises to full magnitude in about 0.1 microsecond. For about 0.5 microsecond the shock wave front instabilities are sufficient to create significant striations in the produced light; this effect diminishes as the thickness
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of the compressed layer increases. Only an about 75 micrometer thick layer of the gas is responsible for the light emission. The shock wave reflects after reaching the window at the end of the tube; this yields a brief increase of light intensity. The intensity then fades.
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charge. The explosion generates a shock wave, which heats the gas to very high temperature (over 10 K; published values vary between 15,000 K to 30,000 K with the best values around 25,000 K). The gas becomes
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Typical argon flash devices consist of an argon-filled cardboard or plastic tube with a transparent window on one end and an explosive charge on the other end. Many explosives can be used;
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Super
Radiant Light (SRL) sources are an alternative to argon flash. An electron beam source delivers a brief and intense pulse of electrons to suitable crystals (e.g. doped
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is produced primarily by compression heating of the surrounding air. Replacement of the air with a noble gas considerably increases the light output; with
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is fairly high, significant heating of the illuminated object can occur. Especially in the case of high explosives, this has to be taken into account.
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High-pressure shock compression of solids VIII: the science and technology of high-velocity impact
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and other processes, while noble gases are monatomic and can only undergo
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Single-use source of very short and extremely bright flash of light
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The device consists of a vessel filled with argon and a solid
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can be also used, argon is favored because of its low cost.
351:"Technical Report: High-Explosive Argon Flash Light Source"
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Lalit C. Chhabildas; Lee
Davison; Yasuyuki Horie (2005).
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To achieve emission, the layer of at least one or two
237:Rudolf Meyer; Josef Köhler; Axel Homburg (2007).
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81:gases, the energy is consumed partially by
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137:and emits a flash of intense visible and
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164:Argon flash is a standard procedure for
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349:Todd Jr, J; Parsons, D (1957-01-11).
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93:then produces the light. The low
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331:. Yarchive.net. 1999-01-29
329:"Argon flash (Arno Hahma)"
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190:are another alternative.
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139:ultraviolet
105:Engineering
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20:Argon flash
393:Explosives
382:Categories
335:2010-03-23
240:Explosives
206:References
99:Flashtubes
87:ionization
40:shock wave
24:argon bomb
130:explosive
79:molecular
75:explosion
57:Although
52:explosion
48:noble gas
194:See also
369:4310914
69:Process
59:krypton
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188:lasers
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388:Argon
63:xenon
44:argon
365:OSTI
309:ISBN
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160:Uses
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