Excitation of resonant oscillations in a solid bar by 30-MeV protons

Abstract

The mechanical response of a metallic bar to pulses of 30-MeV protons has been investigated. It was found that by making the pulse duration short in comparison with the periods of the low-order harmonics of the bar resonant oscillations, vibration amplitudes of the order of 10−11 cm could be measured. The required energy loss by the beam pulses amounted to about 10−5 J, and very simple theoretical considerations suffice to relate quantitatively the deposition of energy in the bar with the amplitudes of its natural vibrational modes.

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