First constraints on coherent elastic neutrino nucleus scattering by CONUS30m
The CONUS experiment, located at the Brokdorf nuclear power plant in Germany, aims at the detection of elastic neutrino nucleus scattering in the fully coherent regime. This talk will describe the experimental setup of four Ge detectors with a very low energy threshold in an elaborate shield at 17 m distance from one of the most powerful reactor cores in the world. A first full spectral analysis of 248.7 kg·d reactor on and 58.8 kg·d reactor off (background) data will be presented, including all relevant systematic uncertainties and a full Monte Carlo description of the background. This data set allows to place the current best limit on the coherent elastic scattering of reactor anti-neutrinos. In addition, the talk will also touch upon the differences to the COHERENT experiment, which is using higher energetic neutrinos from a pion decay-at-rest source, and the potential for beyond standard model physics searches.
(MPI for Nuclear Physics, Heidelberg)
Flavor dependence and radiative corrections in CEvNS30m
One-loop radiative corrections introduce the dependence on the neutrino flavor in CEvNS. To consistently account for radiative corrections, we present the effective field theory of neutrino-lepton and neutrino-quark interactions, embed quarks into nucleons and nucleons into nuclei. We calculate CEvNS cross sections and flavor asymmetries on the spin-0 nucleus at energies below 100 MeV including all kinematic dependence of radiative corrections. We provide a complete error budget accounting for uncertainties at nuclear, nucleon, hadronic and quark levels, and add a perturbative error in quadrature. At 20-100 MeV energies, the uncertainty is limited by the knowledge of neutron distribution inside nuclei. Going to lower energies, hadronic contributions become the dominant source of uncertainty. Our precise predictions can be useful for electroweak measurements at low energies, studies of standard and non-standard neutrino interactions as well as for monitoring of nuclear facilities and precise knowledge of neutrino floor.
(University of Kentucky)