Fusion rate enhancement due to energy spread of colliding nuclei

Abstract

Experimental results for sub-barrier nuclear fusion reactions show cross section enhancements with respect to bare nuclei which are generally larger than those expected according to electron screening calculations. We point out that energy spread of target or projectile nuclei is a mechanism which generally provides fusion enhancement. We present a general formula for calculating the enhancement factor and we provide quantitative estimate for effects due to thermal motion, vibrations inside atomic, molecular or crystal system, and due to finite beam energy width. All these effects are marginal at the energies which are presently measurable, however they have to be considered in future experiments at still lower energies. This study allows to exclude several effects as possible explanation of the observed anomalous fusion enhancements, which remain a mistery.

arXiv comment17 pages with 3 ps figure included. Revtex style

References in corpus (3)

• First Measurement of the He3+He3-->He4+2p Cross Section down to the Lower Edge of the Solar Gamow Peak
• The Cross Section of 3He(3He,2p)4He measured at Solar Energies
• Small Effects in Astrophysical Fusion Reactions

Cited by in corpus (10)

• Solar fusion cross sections II: the pp chain and CNO cycles
• Frontiers in Nuclear Astrophysics
• Solar fusion III: New data and theory for hydrogen-burning stars
• New Enhanced Tunneling in Nuclear Processes
• Indirect methods in nuclear astrophysics with relativistic radioactive beams
• Isospin Effects on Astrophysical S-Factors
• Quantum-tail effect in low energy d+d reaction in deuterated metals
• Fusion reactions in plasmas as probe of the high-momentum tail of particle distributions
• Role of virtual break-up of projectile in astrophysical fusion reactions
• Exponential enhancement of nuclear reactions in condensed matter environment