Comment on Precursors in a Pressure Driven Shock Tube
I commenting on a technical note by W. Zinman, Prof. Weymann referred to our work and incorrectly estimated our diaphragm-probe distance as 100 cm. As a consequence of this estimate, he concluded the following: " . . . that the two probes will measure a stationary state at x = 50 cm ahead of the shock front if the distance of the first probe from the diaphragm is larger than zc == 96 cm . . . It is, therefore, quite curious that Lederman and Wilson find stationary profiles in their shock tube." The over-all length of the driven section is 10 ft, or 305 cm, as stated in Ref. 3. The correct diaphragm-probe distance is 210 cm. Therefore, even according to Professor Weymann's own analysis, it is not at all "curious" that we found stationary profiles in our experiments.