EXA2011

The kinetics of muon-catalyzed-fusion processes (μCF) in pure deuterium D2 gas has been studied with regard to the epithermal effects of muonic dμ-atoms accelerated during the cascade. For this purpose the kinetic energy distribution of dμ atoms in the 1S-state has been calculated using the modified quantum-classical Monte Carlo cascade method developed in [1]. This calculation has confirmed that most dμ atoms are not thermalized. Hence the collisions of such epithermal dμ atoms with deuterium molecules D2 lead to non-resonant formation of ddμ molecules [2] with high rates as compared to for thermalized dμ. However, another process of non-resonant formation may also occur in the presence of non-thermalized dμ-atoms. In parallel with the resonant formation of the ddμ molecule in the weakly bound ro-vibronic (J=v=1) state, the non-resonant formation in the same ddμ-state is also possible. But in this case the emitted Auger electron of the D2 molecule can carry away the released energy only for dμ-atomic collision energies e>I, where I denotes the ionization potential of the D2 molecule. The calculated formation rates in the above-threshold energy region are about one order of magnitude higher than previously obtained in [2]. We have investigated the role of the epithermal non-resonant ddμ formation process described above for μCF in D2 gas. The time spectra of dd-fusion neutrons have been calculated by means of Monte Carlo simulations [3]. It has been shown that similarly to the peak revealed in experiments on μCF in HD mixtures [4], non-resonant ddμ formation by non-thermalized dμ-atoms in the D2 target can also be directly observed in the neutron time spectra at very short initial times, before the complete thermalization of dμ atoms. References [1] M.P. Faifman, and L.I. Men'shikov, Proc. Int. Conf. MCF-07, Dubna, June 18-21, p.233 (2007). [2] M.P. Faifman, Muon Cat. Fus. 4 (1989) 341. [3] A. Adamczak, M. Faifman, Eur. Phys. J. D. 51 (2009) 341. [4] D.V. Balin et. al. Phys. El. Part. At. Nucl., 42, (2011) 185.