Muon Reactions in Liquid Hydrogen and Liquid Deuterium

Abstract

The reactions of muons in liquid hydrogen containing a low concentration of deuterium, pfi-\-d -> dp+p -» (djjip) + -> He 3 +^~(a) or (He 3 ju) + +7(b), and in liquid deuterium containing a low concentration of hydrogen, dtx+p-> (<^iO + ->He 3 +M~(c) or (He 3 /x) + +7(d), and djx+d-* (dfd) + ->H.e*+n+fT(e) or p+t+f(f) t have been investigated using the Chicago 9-in. bubble chamber. Using previously determined values for the formation and fusion rates of the (djjtp) + ion in hydrogen in conjunction with a theoretical determination of the population of the various hyperfine levels in the (djjtp) + ion, reaction (a) is found to occur in (15 ±1.5)% of all {dfxp) + fusion reactions. The formation rate of the (dixd) + ion in liquid deuterium is found to be X drf =(3.6±1.3)Xl0 5 sec" 1 . The fusion rate of the (dfid) + is X d / = (2.5±0.04)X10 5 sec" 1 , and the fraction of muons which, having catalyzed reaction (e), are subsequently bound in a (He 3 /0 + muonic ion is (0.31 ±0.0034). The rate of de-excitation to the lower hyperfine level of the d/j, muonic atom via the reaction dfi(3/2)+d-*d+dn(l/2) has been investigated and found to be (7.9±2.8)X10 5 sec-1 <X (3 / 2 -i/2)<(1.35 ±0.48)X10 6 sec" 1 . The interference of reactions (c), (d), (e), and (f) in the investigation of the spinindependent capture reaction yT-\-d -> n-\-n-\-v is discussed.

Muon-Catalyzed Fusion

“…Note that two distinct classes of observed rates are displayed, corresponding to different contributions from the two d,u hyperfi ne states: (a) Experiments (8a, 14, 54, 55) separate the two hyperfine molecular formation rates X��I" (b) Although hyperfi ne populations are not always known exactly fo r experiments (26,52,53,56,57), they mainly correspond to the steady-state situation and measure an average molecular formation rate Xddl' that is a superposition of molecular fo rmation rates Zdw Within this data set there seems to be a normalization problem in the pioneering Dubna experiment (52), which obtains a similar T dependence but has a rate lower by a fa ctor of '" 4 than all subsequent experiments. Bubble chamber results (58) are not shown in Figure 5, but if interpreted properly…”

“…In order to measure and interpret unambiguously the basic nuclear capture process (,u-p -+ nv) in hydrogen and deuterium, the different atomic and molecular processes induced by ,uin hydrogen mixtures had to be understood (7). Surprisingly, one of these "back ground" reactions showed a puzzling behavior: thc rate for forming the dd,u "mesomolecule" (muonic molecular ion) that precedes the fu sion was found experimentally to be large and to have a strong temperature dependence (8). The previously calculated Auger process (6), in which the energy released upon binding (typically tens to hundreds of eV) is carried off by an ej ected electron, is more than an order of magnitude slower and is not strongly energy dependent.…”

Muon catalysis and nuclear breeding

“…доли процента!) слабосвязанное состояние в мезомолекуле либо исчезает, либо становится настолько глубо ким, что полностью разрушаются условия эффективного образования молекул в резонансной реакции (24).…”

“…табл. III) и измеренные ранее в жидком дейтерии [17,23,24]. Гипотеза Э. А. Весмана была предложена именно для объяснения результатов этих опытов, в частности, тем пературной зависимости полученной в этих экспериментах.…”

Muonic-atom scattering from hydrogenic liquids in an incoherent approach

“…Many experiments in low-energy muon physics were performed in the liquid mixtures of hydrogen isotopes. In particular, such hydrogenic targets were employed for studying the muon-catalyzed pd and pt fusion in the muonic molecules pdµ and ptµ (see, e.g., [1][2][3][4][5]). The yields of different products from these fusion reactions strongly depend on the populations of hyperfine states of the muonic molecules.…”