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On Mechanisms of Low-Energy Nuclear NUCLEAR PHYSICS 37 ON MECHANISMS OF LOW-ENERGY NUCLEAR-CHEMICAL PROCESSES 1,2Serge Timashev 1Karpov Institute of Physical Chemistry, http://www.karpovipc.ru Moscow 105064, Russian Federation 2National Research Nuclear University MEPhI, https://mephi.ru Moscow 115409, Russian Federation [email protected] Abstract. It is shown that a wide variety of low-energy nuclear transformations studied under conditions of a nonequilibrium low-temperature glow discharge plasma and laser ablation of metals in aqueous media can be understood on the basis of the concepts of the dynamic interrelation between the electron and nuclear subsystems of an atom. The initiating role in such processes belongs to electrons a sufficiently large kinetic energy eE ~ 3-5 eV (by chemical scales), which they can acquire under the indicated conditions. Inelastic scattering of electrons by nuclei in according to weak nuclear interaction becomes possible in the collision of such electrons with ions or plasma atoms (here we assume that the nuclei are not related to “K-capture” nuclei). At the first stage of such a nuclear-chemical interaction, a nucleus arise, the charge of which is one unit less than the charge of the initial nucleus, and nuclear matter is locally disrupted: the nuclear mass in this case is insufficient to preserve nuclear matter in the base state of interacting nucleons. Under such anomalous excitations of nuclear matter, which are characterized as the states of “inner shake-up” or isu-state, the relaxation dynamics of the nuclei is initiated by weak nuclear interactions. Such nuclei, being β-active (“β-nuclei”), can have sufficiently long lifetimes and effectively participate in nuclear reactions (as the β-neutron and β-dineutron introduced into consideration). If the initial nucleus is radioactive, the decay of “β-nuclei” will occur with a probability many orders of magnitude greater than the decay probability of the original nuclei. As an example, the nuclear- chemical transformations realized in the E-CAT reactor of Andrea Rossi are also considered. Key words: low-temperature plasma, laser ablation of metals in aqueous media, β-nuclei, low-energy nuclear-chemical transformation, u- and d-quarks, Feynman diagrams of the initiating radioactive decay. PACS 25.10.+s Bibliography – 43 references Received 25.5.2017 RENSIT, 2017, 9(1):37-51 DOI: 10.17725/rensit.2017.09.037 CONTENTS 1. INTRODUCTION 1. INTRODUCTION (37) Beginning with the work of Fleischmann, Pons 2. ELECTRONIC FACTOR IN INITIATING NUCLEAR and Hawkins [1] on observation of excessive heat PROCESSES (39) generation during the electrolysis of D2O heavy 3. POSSIBLE MECHANISMS OF NUCLEAR-CHEMICAL water with a Pd cathode, when the generation of REACTIONS (42) neutrons and tritium was recorded, it became clear 3.1. MECHANISM OF NUCLEAR FUSION (43) that the problem of establishing the mechanism – 3.2. MECHANISM OF e -CATALYSIS (44) of the occurring nuclear transformations could 3.3. HARPOON MECHANISM (45) become a key to solving the complex of problems 4. NUCLEAR CHEMICAL PROCESSES IN ANDREA that arose in connection with the phenomenon of ROSSI'S E-CAT REACTOR (46) low-energy nuclear reactions (LENR). One of the 5. CONCLUDING REMARKS(48) first attempts to solve this problem was associated REFERENCES (49) with the possibility of the existence of a stable dineutron with a binding energy εdn less than RENSIT | 2017 | Vol. 9 | No. 1 38 SERGE F. TIMASHEV NUCLEAR PHYSICS 3.01 eV (for the deuteron not to be radioactive) With time, it became clear that in order to [2]. In the experiment [1], the arising a dineutron understand the results of [1], as well as many as a result of the interaction of an activated later works on initiating low-energy nuclear electron with a deuteron under conditions of reactions (LENR) and accelerating radioactive α electrolysis of heavy water could be considered as and β decays, including under low-temperature the first stage preceding the reaction of formation plasma conditions [7-9], and when laser ablation of tritium during the interaction of the dineutron of metals in aqueous media [10-13], the idea with the deuteron. However, there remained of a stable dineutron should be abandoned, questions. It was unclear whether it is possible to and it is necessary to involve other hypotheses. actually activate the electrons in the conditions of At the same time, the results of [14] in which electrolysis of heavy water on a palladium cathode the spectrum of the "lost mass" in the process to the necessary (what exactly?) energies, and 6Li(π–, p)5H (see Fig. 1) with the kinetic energy whether there really is a dineutron. The possibility of π–-mesons equal to 125 MeV was investigated, of the 2n nucleus existence was discussed back continue to cause surprise. It follows from Fig. 1, in the early 1960s when studying the T(d, 2n)3He a fixed maximum in the region of the lost mass process using the 27Al(2n, γ)29Al reaction for the from zero to –5 MeV/c2 could well correspond to detection of 2n particles [3]. However, in [4], which a hypothetical dineutron with a binding energy of appeared shortly after the publication of [3], the εdn ≈ 3MeV. However, in this case, the probability results of a similar experiment were reported and of the occurring a dineutron in the reaction it was reported that the yield of 29Al, confirming involving a π–-meson would have an order of the reality of the existence of 2n nucleus, was observed only at the background level. Moreover, it was known, based on general considerations, that the 2n nucleus can not exist in principle. Since there is a bound state in the neutron-proton system with a binding energy εD = 2.22 MeV and spin S = 1, and also there is a virtual level with energy 70 keV and spin S = 0, for the system of two neutrons only the existence of a virtual state with spin S = 0 due to the charge independence of the nuclear forces (isotopic invariance), is possible [5]. But in this state there should be a weak repulsion, and the state with S = 1 can not exist due to the Pauli principle. Nevertheless, in this review [5], based on an analysis of the experimental data available at that time (1965), an upper estimate of the cross section for the formation of a nuclear stable dineutron, s < 0.001-0.01 mb, was still given, although this estimate practically excluded the possibility of manifestation of 2n in any experiments. This estimate was confirmed by the result of a much later experiment [6], in which for the cross section Fig. 1. The missing-mass spectra for the reaction 6Li(π–, p)5H of occurring a stable dineutron in the interaction [14]. The constant line at the bottom corresponds to the background. of cold neutrons with deuterons in the reaction The phase-space distributions shown are as follows: (a) curve 1, fit n + d → 2n + p, we obtained: σ ≤ 1 mcb. for 5H → 3H + n + n; (b) best-fit curve as sum of curve 1 for 5 H → 3H + n + n and curve 2 for 5H → 3H + 2n. No. 1 | Vol. 9 | 2017 | RENSIT ON MECHANISMS OF LOW-ENERGY 39 NUCLEAR PHYSICS NUCLEAR-CHEMICAL PROCESSES magnitude higher than the values indicated above, atom (i.e., the mass of the whole atom, not the for unknown reasons. nucleus) and the total mass of the decay products In subsequent years, in order to understand [23, 24]. Usually, when considering the mechanisms the results of many papers in which low-energy of these low-energy nuclear processes and the A nuclear transformations and low-temperature decay of atomic nucleus Z N (Z and A are the plasma accelerated decays of radioactive nuclei atomic number and mass number of the nucleus were investigated, attempts were repeatedly made N, respectively), nuclear matter is represented in to introduce neutral particles with a baryon number the form of interacting nucleons. For example, of two (or one) that were the weakly coupled or in the K-capture, when the electron of the inner resonant state of the deuteron (or proton) with shells of the atom interacts with the surface of an electron or a neutron with a neutrino. Such the nucleus and a new daughter nucleus is formed, particles could participate in low-energy nuclear the nucleon structure of nuclear matter does not reactions, since for such a type of particles change. At the initial, irreversible stage of this there would be no problem of overcoming the process, the electron emits a neutrino ν when "Coulomb barrier" in nuclear interactions. We interacting with the nucleus surface. The formed do not consider such possibilities here, since in virtual vector W–-boson, which is introduced into accordance with the concepts of nuclear physics, the nuclear matter, is transformed into a d-quark electron and neutrino localization on nuclear when interacting with the u-quark of one of the scales ~ 10-13 cm would have an abnormally high, protons, as a result of which this proton turns A physically incredible uncertainty in the pulses into a neutron, and the nucleus Z -1 M is formed. [15]. However, the situation can drastically change In this paper, it is shown that the problems of when the K-capture is energetically forbidden establishing the possible mechanisms of LENR (it is such cases that are considered below), but processes discussed above can be understood the electron has a sufficiently large (by chemical on the basis of the concepts of the interrelation standards) kinetic energy Ee ~ 3-5 eV, as it can between the electronic and nuclear subsystems be realized in low-temperature plasma. Under of an atom [16-20], which determines the these conditions, when the process of ionization possibility of initiating the entire variety of of electron shells by such electrons is not yet nuclear transformations, including those studied realized, then, during scattering of electrons with in mentioned works [7-13], as well as realized in the indicated kinetic energy and the corresponding the Andrea Rossi E-CAT reactor [21, 22].
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