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We calculate the transition radiation process $ u to u gamma$ at an interface of two media. The neutrinos are taken to be with only standard-model couplings. The medium fulfills the dual purpose of inducing an effective neutrino-photon vertex and of modifying the photon dispersion relation. The transition radiation occurs when at least one of those quantities have different values in different media. The neutrino mass is ignored due to its negligible contribution. We present a result for the probability of the transition radiation which is both accurate and analytic. For $E_ u =1$ MeV neutrino crossing polyethylene-vacuum interface the transition radiation probability is about $10^{-39}$ and the energy intensity is about $10^{-34}$ eV. At the surface of the neutron stars the transition radiation probability may be $sim 10^{-20}$. Our result on three orders of magnitude is larger than the results of previous calculations.
We discuss the transition radiation process $ u to u gamma$ at an interface of two media. The medium fulfills the dual purpose of inducing an effective neutrino-photon vertex and of modifying the photon dispersion relation. The transition radiation
We show that the more energetic superluminal neutrinos with quadratically dispersed superluminalities delta=beta^2-1, for beta=v/c where v is the neutrino velocity, also lose significant energy to radiation to the u+e^-+e^+ final state in travelling
Light sterile neutrinos represent a well-motivated extension of the 3-neutrino paradigm. However, the impressive agreement between standard cosmology and data casts doubts on their existence. Here we present a class of scenarios that robustly avoids
Advanced linear accelerator design may use Optical Transition Radiation (OTR) screens to measure beam spot size; for instance, such screens are foreseen in plasma based accelerators (EuPRAXIA@SPARC_LAB) or Compton machines (Gamma Beam Source@ELI-NP).
We study the threshold production of two pions induced by neutrinos in nucleon targets. The contribution of nucleon pole, pion and contact terms is calculated using a chiral Lagrangian. The contribution of the Roper resonance, neglected in earlier studies, has also been taken into account.