First upper limits on neutrino electromagnetic properties from the CONUS experiment

We report first constraints on neutrino electromagnetic properties from neutrino-electron scattering using data obtained the CONUS germanium detectors, i.e. an upper limit effective magnetic moment and millicharge. The electron antineutrinos are emitted 3.9 GW$_\mathrm{th}$ reactor core of Brokdorf nuclear power plant in Germany. low background detectors positioned at 17.1 m distance center. analyzed set includes 689.1 kg$\cdot$d collected during ON periods 131.0 OFF energy range 2 to 8 keV$_{ee}$. With current statistics, we able determine $\mu_\nu < 7.5\cdot10^{-11}\,\mu_B$ 90% confidence level. From this can derive bound millicharge $\vert q_{\nu}\vert 3.3\cdot10^{-12}\,e_0$.