Materials Science Forum, Vol.445-6, 343-345, 2004
Correlation between the Doppler broadening S parameter and ortho-positronium formation probability in polymers
Various kinds of polymers were systematically studied by the combination of positron lifetime and coincident Doppler broadening spectroscopy. The correlation between the S parameter and ortho-positronium (o-Ps) fraction (I(o-Ps)), strongly dependent on the chemical element that the polymers contain, enabled us to separately extract the Doppler broadening profiles of positrons and positronium.