Related papers: X17: A new force, or evidence for a hard $\gamma +…
Recently, it was suggested that the 17 keV neutrino does not mix with the electron neutrino in the weak interactions. Instead, the $\beta$ decay mode involving the 17 keV neutrino is induced by a completely new interaction, presumably…
The mechanism behind fast intersystem crossing in transition-metal complexes is shown to be a result of the dephasing of the photoexcited state to the phonon continuum of a different state with a significantly different transition…
Experiments involving phase coherent dynamics of networks of spins, such as echo experiments, will only work if decoherence can be suppressed. We show here, by analyzing the particular example of a crystalline network of Fe8 molecules, that…
A number of popular extensions of the Standard Model of particle physics predict the existence of doubly charged scalar particles $X^{\pm\pm}$. Such particles may be long-lived or even stable. If exist, $X^{--}$ could form atomic bound…
The overabundance of high-energy cosmic positrons, observed by PAMELA and AMS-02, can be considered as the consequence of dark matter decays or annihilations. We show that recent FERMI/LAT measurements of the isotropic diffuse gamma-ray…
Long-lived high-spin super- and hyper-deformed isomeric states, which exhibit themselves by abnormal radioactive decays, have been observed using the 16O + 197Au and 28Si + 181Ta reactions. They make it possible to understand the…
We study the decoherence of a coupled quantum system consisting of a central spin and its correlated environment described by a general $XY$ spin-chain model. We make it clear that the evolution of the coherence factor sensitively depends…
The protons and neutrons in a nucleus can form strongly correlated nucleon pairs. Scattering experiments, where a proton is knocked-out of the nucleus with high momentum transfer and high missing momentum, show that in 12C the…
The microscopic justification of the emergence of SU(3) symmetry in heavy nuclei remains an interesting problem. In the past, the pseudo-SU(3) approach has been used, with considerable success. Recent results seem to suggest that the key…
It is shown that the Coulomb correlation problem for a system of two electrons (two charged particles) in an external oscillator potential possesses a hidden $sl_2$-algebraic structure being one of recently-discovered quasi-exactly-solvable…
The sub-barrier fusion hindrance has been observed in the domain of very low energies of astrophysical relevance. This phenomenon can be analyzed effectively using an uncomplicated straightforward elegant mathematical formula gleaned…
We discuss the decays X^* -> Xe^+e^- (``Dalitz decays'') of excited heavy mesons into their ground states and an electron-positron pair. We argue that the measurement of the invariant mass spectrum of the lepton pair gives clear indication…
Uncertainties in the nuclear transition matrix elements $M^{(0\nu)}$ and $M^{(0N)}$ of the double-positron emission $(\beta ^{+}\beta ^{+})_{0\nu}$ and electron-positron conversion $(\varepsilon \beta ^{+})_{0\nu}$ modes due to the exchange…
A signal of two leptons and missing energy is challenging to analyze at the Large Hadron Collider (LHC) since it offers only few kinematical handles. This signature generally arises from pair production of heavy charged particles which each…
Analytical solutions of the Dirac equation in an external electromagnetic field are found such that according to the field-theoretic interpretation electron-positron pairs are trapped for a period of time. The naive one-particle…
We present a simple explanation of the underlying physics in the use of hyperon decay data to obtain information about proton spin structure. We also present an alternative input using nucleon magnetic moment data and show that the results…
Using equivalencies between different models we reduce the model of two spin-1/2 Heisenberg chains crossed at one point to the model of free fermions. The spin-spin correlation function is calculated by summing the perturbation series in…
We consider the hypothesis that the recently reported anomaly in the time structure of signals in the KARMEN experiment is due to the production of a light photino (or Zino) which decays radiatively due to violation of $R$-parity. Such a…
A recent high-resolution $\alpha$, $X$-ray, and $\gamma$-ray coincidence-spectroscopy experiment offered first glimpse of excitation schemes of isotopes along $\alpha$-decay chains of $Z=115$. To understand these observations and to make…
The discrepancy between the neutron lifetimes measured in the beam and trap experiments can be explained via the neutron $n$ conversion into mirror neutron $n'$, its dark partner from parallel mirror sector, provided that $n$ and $n'$ have…