Nuclear fusion driven by Coulomb explosion of methane clusters

Multielectron ionization and Coulomb explosion of methane clusters (CA₄)_n, A = H, D, and T, in very intense (I = 10¹⁸-10¹⁹ W cm^-2) laser fields were studied using classical dynamics simulations. The products of Coulomb explosion involve light A⁺ ions (p, d, and t nuclei) with energies up to 20 keV, C⁴⁺ ions at I = 10¹⁸ W cm^-2, and C⁶⁺ ions (carbon nuclei) with energies up to 110 kev at I = 10¹⁹ W cm^-2. Important advantages of nuclear fusion driven by Coulomb explosion of methane (C⁴⁺A₄⁺)_n and (C⁶⁺A₄⁺)_n heteronuclear clusters pertain to energetic effects, with the heavy multielectron ions driving the light H⁺, D⁺, or T⁺ ions (d or t nuclei) to considerably higher energies than for homonuclear deuterium clusters of the same size, and to kinematic effects, which result in a sharp high-energy maximum in the light-ion spectrum for the (C⁴⁺A₄⁺)_n and(C⁶ A₄⁺)_n clusters. We studied the energetics of Coulomb explosion in conjunction with isotope effects on the product A⁺ and C^k+ ions energies and established the cluster size dependence of dd and dt fusion reaction yields from an assembly of Coulomb-exploding clusters. The C⁶⁺ nuclei produced by Coulomb explosion of (C⁶⁺D₄⁺)_n (n = 5425) clusters are characterized by an average energy of E_av = 65.2 kev and a maximum energy of E_M = 112 keV. A search was undertaken for the ¹²C⁶⁺ + ¹H⁺ fusion reaction of astrophysical interest.