X-Ray-Flash

Tables 2.1 and 2.2 show that theory enables detonation velocities to be calculated in close agreement with those observed experimentally. This, unfortunately, is not a critical test of the theory as velocities when calculated are rather insensitive to the nature of the equation of state used. A better test would be to calculate the peak pressures, densities and temperatures encountered in detonation, and compare these with experimental results. The major difficulties here are experimental. Attempts to measure temperatures in the detonation zone have not been very successful, but better results have been obtained in the measurement of densities and pressures. Schall introduced density measurement by very short X-ray flash radiography and showed that TNT at an initial density of 1 -50 increased 22% in density in the detonation wave. More recently detonation pressures have been measured by Duff and Houston using a method (introduced by Goranson) in which the pressure is deduced from the velocity imparted to a metal plate placed at the end of the column of explosive. Using this method, for example, Deal obtains the detonation pressures for some military explosives recorded in Table 2.3. More...

Jets, GRB connection, X-ray flashes, HETE-2 data (Lamb et al. 2003). 

L. Deffet M. de Coster, Explosifs (Belgium) 5, 106-13(1952) Chim Ind (Paris) 69, 490(1953) CA 49, 6605-07 (1955) (Initiation to deton of solid expls by X-ray flashes. The method consisted of producing a flux of X-rays of an extremely short period, such as less than 1 microsecond, using detonators contg 0.45 g MF 0.75 g TNT. Radiographs taken at various times after beginning of deton, such as 7 to 24 microsecs, showed that expansion of deton gas occurs laterally and that the forward part of the detonator hardly moved. The deton of MF was slowed down by that of TNT. It has been shown that the form... 

The determination of the maximum detonation pressure pi, in equation (2d) has been studied by X ray measurements. While the detonation velocity can be measured directly by electronic recorders or by the - Dautriche Method, there is no direct measurement possibility for the fume velocity W, but it can be estimated by the flow off angle of the fumes behind the wave front this angle can be taken from X ray flash photographs. The relation between Dand M/is... 

By using special X-ray tubes and very fast high-voltage circuitry, it is possible to generate and trigger ultrashort X-ray flashes down to the millimicrosecond range. 

These X-ray flashes are an important means of short-time photography because they enable fast occuring phenomena to be recorded by means of X-ray photographs. 

Frungel F, Alberti H, Thorwart W (1962) High-speed X-ray flash cinematography of small objects. J SMPTE-Soc Motion Picture Telev Eng 71 90-92... 

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