Random propagation times for ultrasonics through polyethyilene

Low power ultrasonics are used for testing high density polyethylene pipe material. Attenuation and velocity give valuable information on the material in situ without damages. In this paper we revisit recent data frequency band (4,10) megahertz. We prove that propagation is equivalent to random delays following stable probability laws. Moreover, emergence of a companion noise non-detectable by devices compliant with law conservation energy.