Muon catalyzed fusion in 3-K solid deuterium

Abstract

Muon catalyzed fusion in deuterium traditionally has been studied in gaseous and liquid targets. The TRIUMF solid-hydrogen-layer target system has been used to study the fusion reaction rates in the solid phase of D 2 at a target temperature of 3 K. Products of two distinct branches of the reaction were observed: neutrons by a liquid organic scintillator and protons by a silicon detector located inside the target system. The effective molecular formation rate from the upper hyperfine state of d and the hyperfine transition rate have been measured: 3 2 ϭ2.71(7) stat (32) syst s Ϫ1 and 3 2 1 2 ϭ34.2(8) stat (1) syst s Ϫ1 . The molecular formation rate is consistent with other recent measurements, but not with the theory for isolated molecules. The discrepancy may be due to incomplete thermalization, an effect that was investigated by Monte Carlo calculations. Information on branching ratio parameters for the s and p wave dϩd nuclear interaction has been extracted.

Differential cross sections for muonic atom scattering in solid hydrogenic targets

“…Townsend minima, which is apparent at about 10 eV. This mechanism has been used for the production of the energetic (1-10 eV) dµ and tµ beams at TRIUMF [1,2,3,4,5,6]. The calculated differential cross sections establish the basis for accurate simulations of the emission of such muonic-atom beams.…”

“…The solid hydrogenic targets have been used for the production of the muonic hydrogen atom beams, which have been applied to the time-of-flight measurements of various muonic-atom and muonic-molecular processes (see e.g., Refs. [1,2,3,4,5,6]). The bulk hydrogenic crystals are employed in the investigations of muon-catalyzed fusion of the hydrogen isotopes at high target densities and for various populations of the rotational molecular levels [7,8,9,10,11,12,13].…”

“…Monte Carlo simulations of such experiments, which used the perfect-gas model of a target and the available differential cross sections [16,17] for the muonic atom scattering from hydrogen-isotope nuclei, did not reproduce the experimental low-energy ( 1 eV) data. Moreover, even the use of the cross sections for scattering from isolated hydrogenic molecules [18,19] did not lead to an agreement between theory and experiment [1,8]. Thus, it is necessary to take into account condensed-state effects of the muonic atom scattering in the solids.…”

Survey of muon stripping in the muon-catalyzed $d-d$ fusion cycle in pure deuterium

“…The subsequent deexcitation of the dµ muonic atom occurs via Stark, Auger, scattering, radiative, and transfer * Correspondence: motavali@umz.ac.ir processes, which occur on the 100 ps time scale [17,18]. The energy difference between the two hyperfine states of the dµ muonic atom (F = 3/2, 1/2) is 48.5 MeV [19].…”

“…The subsequent deexcitation of the dµ muonic atom occurs via Stark, Auger, scattering, radiative, and transfer * Correspondence: motavali@umz.ac.ir processes, which occur on the 100 ps time scale [17,18] [19,20]. In general, λ is given by…”