Eur. Phys. J. A (2006) 27: 83-88
https://doi.org/10.1140/epja/i2006-08-012-y

Nuclear Physics in Astrophysics II

Experimental and theoretical screening energies for the ²H(d, p)³H reaction in metallic environments

¹ Institut für Atomare Physik und Fachdidaktik, Technische Universität Berlin, Hardenbergstr. 36, 10623, Berlin, Germany
² Institute of Physics, University of Szczecin, Szczecin, Poland
³ TRIUMF, Vancouver, Canada

^* e-mail: czerski@kalium.physik.tu-berlin.de

Received: 13 July 2005
Accepted: 20 December 2005
Published online: 23 February 2006

Abstract

The study of the ²H(d, p)³H reaction at very low energies in deuterized metallic targets provides a unique possibility to test models of the electron screening developed for dense astrophysical plasmas. Here, we compare the experimental screening energies obtained by our group as well as by other authors for different target materials with theoretical predictions based on an improved dielectric function theory. The calculations are performed within the self-consistent regime and include polarization of both quasi-free and bound electrons. Additionally, the cohesion screening, arising from different binding energies of deuterons and α-particles in crystal lattices, is taken into account. The proposed theory predicts only a weak material dependence of the screening energy in agreement with our experimental results but fails in the absolute strength of the effect by a factor of 2. The projectile-velocity dependence of the screening energy corresponding to the transition from the weak-screening regime to the strong-screening limit is discussed.