Benchtop D+D LENR at Lawrence Berkeley Lab/MIT

  • New preprint ---

    "Investigation of light ion fusion reactions with plasma discharges"


    The scaling of reaction yields in light ion fusion to low reaction energies
    is important for our understanding of stellar fuel chains and the development
    of future energy technologies. Experiments become progressively more
    challenging at lower reaction energies due to the exponential drop of fusion
    cross sections below the Coulomb barrier. We report on experiments where
    deuterium-deuterium (D-D) fusion reactions are studied in a pulsed plasma in
    the glow discharge regime using a benchtop apparatus. We model plasma
    conditions using particle-in-cell codes. Advantages of this approach are
    relatively high peak ion currents and current densities (0.1 to several A/cm^2)
    that can be applied to metal wire cathodes for several days. We detect neutrons
    from D-D reactions with scintillator-based detectors. For palladium targets, we
    find neutron yields as a function of cathode voltage that are over 100 times
    higher than yields expected for bare nuclei fusion at ion energies below 2 keV
    (center of mass frame). A possible explanation is a correction to the ion
    energy due to an electron screening potential of 1000+/-250 eV, which increases
    the probability for tunneling through the repulsive Coulomb barrier. Our
    compact, robust setup enables parametric studies of this effect at relatively
    low reaction energies.

  • " Detection of Xrays induced by high energy electrons (15 keV) in a scanning electron microscope showed a surface composition of palladium with significant contributions from carbon (30 at%) and oxygen (20 at%) in the top 100 nm. The control sample wires had a near-surface composition with smaller contributions from oxygen and carbon (14 at% each)

    Research question .. did the carbon come from stainless steel?

  • Good to see this fascinating additional experimental work casting light on electron screening in lattices. That is one of the more plausible ways in which LENR might be encouraged to happen. Sure, D+D is neutronic, but at low rates, with the effect only occasionally observed, that would be compatible with some of the results. Others - well - we know for sure that not all LENR claimed anomalies are correctly interpreted, because the underlying interpreting theories are so incoherent.

  • electron screening... is one of the more plausible ways that LENR might.. happen

    Shenkel at al,2019 seem to have some inconsistency.. incoherence about Reference 8.

    Is it included in References 5-11 or not?

    I might ask them whether their results are consistent or inconsistent

    with the 2005 Lipson Rusetski Miley and Karabut's 650 Ev result.

    ""But an electron screening potential of ~1000 eV is not consistent with established theories of electron screening, which reproduce measured values from gas phase experiments of ~27 eV [1, 5-11]. The value of Ue from our measurements in the neutron channel is consistent with earlier results in a similar glow discharge plasma regime and measurements of protons from D-D fusion reactions [8].""

    [8] A. G. Lipson, A. S. Rusetski, A. B. Karabut, and G. Miley, Journal of Experimental and Theoretical Physics 100 , 1175 (2005).

    Lipson et al stated a mystery in 2005

    ""Note that so far the screening mechanism of DD-reaction in metals remains a mystery because there is no developed approach

    to explain Ue > 100 eV (strongly above adiabatic limit) by normal valence electron screening.

    Here we note that metal host inner electron shells may somehow take part in the screening""

    The 2019 authors present no plausible explanation for the mystery that Lipson et al stated in 2005, 14 years earlier.

    but restate it as ""~1000 eV is not consistent with established theories of electron screening""

    Perhaps the increased neutron emissions in in the 2019, 2005 exptal setups are not due to electron screening at all.