The articles by Barinov et al telling of the experiment and published in Phys Rev Letters and Phys Rev C, can be found from arXiv (see this and this). A thorough discussion of standard nuclear physics predictions for the reaction rate of the reaction can be found in the article "The gallium anomaly revisited" by Kostensalo et al (see this).
Gallium anomaly is reported to be consistent with the sterile neutrino explanation stating that part of the electron neutrinos from the beta decay of 51Cr transform to their sterile counterparts so that the reaction rate is reduced.
The already discussed MicroBoone experiment (see this) however seems to exclude inert/sterile neutrinos.
- What was reported is the following. Liquid Argon scintillator was used as a target. Several channels denoted by 1eNpMπ where N=0,1 is the number of protons and M=0,1 is the number of pions, were studied. Also the channel 1eX, where "X" denotes all possible final states was studied. It turned out that the rate for the production of electrons is below or consistent with the predictions for channels 1e1p, 1eNp0π and 1eX.
Only one channel was an exception and corresponds to 1e0p0π. This anomalous scattering without hadrons in the final state was interpreted in terms of the scattering of νe on dark weakly interacting matter. Also the neutrino must be dark and the values of heff must be identical for this dark matter and dark neutrino if they interact.
- The strange scattering in the 0-proton channel would take place from weakly interacting matter, which is dark in the sense that it has non-standard value of effective Planck constant heff=nh0: this proposal has a number theoretic origin in the TGD framework. Darkness implies that the particles with the same value of heff appear in the vertices of scattering diagrams. Dark and ordinary particles can however transform to each other in 2-vertex and this corresponds to mixing. The identification of what this weakly interaction dark matter might be, was not considered.
These findings inspire the question whether the inert neutrinos are dark neutrinos in the TGD sense and therefore have heff>h? The mixing of the incoming neutrinos with their dark variants would take place in the 71Ga experiment. Dark neutrinos would not interact with 71Ga target since neutrons inside the 71Ga nuclei are expected to be ordinary so that the νe+n\rightarrow p+e- scattering rate would be lower as observed.
The identification of sterile neutrinos as dark neutrinos can be consistent with the Micro-Boone anomaly if one can identify the weakly interacting dark matter.
- Dark neutrons should not be present in the liquid Argon. Could the weakly interacting dark matter be meson-like states consisting of dark d quarks or anti-u quarks? Since the scattering from them cannot contribute to the nuclear weak interaction, these flux tubes must be outside Argon nuclei. By the large value of heff, they would connect Argon nuclei.
- The TGD inspired model of nuclei describes them as nuclear strings consisting of nucleons connected by meson-like strings with quark and antiquark at its ends. The model of "cold fusion" (see this, this and this) inspired the proposal that dark nuclei consisting of dark protons connected by dark meson-like strings are formed in a water environment and give rise to what might be called dark nuclei.
The nuclear binding energy of the dark nuclei is scaled down by the ratio of the length scale defined by the distance between dark protons to nuclear length scale. The decay of dark nuclei to ordinary nuclei liberates more nuclear energy than ordinary nuclear reactions. Also strings of nuclei connected by dark meson-like flux tubes can be imagined. One can also consider flux tube bonded clusters of nuclei.
- The TGD based model for living matter involves in an essential way the formation of dark proton sequences at flux tubes when water is irradiated in presence of gel, by say infrared light.
Could these dark flux tube bonds between nuclei relate to hydrogen bonds and hydrogen bonded clusters of water molecules? Could the "Y...H" of the hydrogen bond Y...H-X actually correspond to a dark meson-like flux tube bond between nuclei of Y and H? Could the attractive nuclear interaction between Y and X generated in this way increase the density of the liquid phase and explain the strange finding that the density of water above freezing point is higher than the density of the solid state?
Interestingly, according to the Wikipedia article (see this), Ga has some strange thermodynamic properties. The density of Ga above freezing point is higher than that of solid state. This property is shared also by water, silicon, germanium, bismuth, and plutonium. Ga has a strong tendency to supercool down to temperatures below 90 K.
- This suggests that liquid phases could in some situations form structures connected by dark meson-like flux tubes. If heff>h phases are generated as long range quantum fluctuations at quantum criticality and if quantum criticality is behind the thermodynamic criticality, this could happen near or above criticality for solid-liquid phase transition and even solid-gas phase transition.
If this kind of flux tubes connecting Argon nuclei (Argon does not have anomalous thermodynamics) are present in a liquid Argon detector, they explain the observed anomalous contribution to neutrino-Argon scattering.
Also in Gallium this could be the case as suggested by the higher density above freezing point. Could one detect the anomalous scattering of neutrinos from the proposed flux tube bonds connecting Ga atoms and study the anomalous scattering as a function of the temperature?
For a summary of earlier postings see Latest progress in TGD.