Nuclear Reaction Rates in a Plasma The Effect of Highly Damped Modes.pdf

Nuclear Reaction Rates in a Plasma: The Effect of Highly Damped Modes Merav Opher1∗ , Reuven Opher2† 1Physics and Astronomy Department T-Plasma Group, 1-130 Knudsen University of California, Los Angeles, CA 90095-1547, U.S.A 2Instituto Astronˆomico e Geof´ısico - IAG/USP, Av. Miguel St´efano, 4200 CEP 04301-904 S˜ao Paulo, S.P., Brazil (February 1, 2008) The fluctuation-dissipation theorem is used to evaluate the screening factor of nuclear reactions due to the electromagnetic fluctuations in a plasma. We show that the commonly used Saltpeter 0 factor is obtained if only fluctuations near the plasma eigenfrequency are assumed to be important 0 (ω ∼ ωpe ≪ T (¯h = kB = 1)). By taking into account all the fluctuations, the highly damped ones, 0 2 with ω ωpe , as well as those with ω ≤ ωpe , we find that nuclear reaction rates are higher than those obtained using the Saltpeter factor, for many interesting plasmas. n u PACS numbers: 52.25.Dg, 95.30.Qd J 2 2 I. INTRODUCTION 1 v 6 It is known that fusion reactions within a plasma are enhanced. This is due to the fact that ions in a plasma are 2 not “naked”, but are surrounded by ele