Accession Number:

AD0355563

Title:

ATOMIC PARTICLE IRRADIATION TECHNIQUES

Descriptive Note:

Interim rept. no. 1, 29 May 63-28 Feb 64,

Corporate Author:

ION PHYSICS CORP BURLINGTON MA

Personal Author(s):

Report Date:

1964-11-01

Pagination or Media Count:

45.0

Abstract:

A series of electron irradiations was performed with a 1.5 MeV Van de Graaff accelerator operated in a pulsed mode. The beam could be focused to approximately 2 mm dia. with pulse duration of 40 microseconds and with beam currents ranging from 0.2 to 0.5 amperes. Targets of tantalum and beryllium appeared undamaged by such pulses whereas lead and tin experienced severe cratering. These effects are in approximate agreement with a simple theory of heating, which took into account target density, melting point, specific heat and electron penetration. Photographs of the ejection of molten metal during irradiations are presented. A high-speed framing camera has recorded breakdown events in lucite during irradiation. The films show fluorescence of the target with periodic breakdown as the irradiated volume discharges to ground. These breakdowns result in permanent damage to the lucite, taking the form of the well known Lichtenberg figure. A focused pulse results in concentration of the patterns with severe foaming of the irradiated surface due to rapid evolution of gas. It is proposed that further experiments be performed with metal and dielectric targets. Of particular interest will be the effect of internal breakdown and localized heating upon explosive materials. Author

Subject Categories:

  • Lasers and Masers
  • Particle Accelerators

Distribution Statement:

APPROVED FOR PUBLIC RELEASE