The result of the neutrino magnetic moment measurement at the Kalinin Nuclear Power Plant (KNPP) with GEMMA spectrometer is presented. The antineutrino-electron scattering is investigated. A high-purity germanium detector with a mass of 1.5 kg placed at a distance of 13.9 m from the 3 GWthreactor core is exposed to the antineutrino flux of2.7×10131/cm2/s. The recoil electron spectra taken in 18134 and 4487 hours for the reactor ON and OFF periods are compared. The upper limit for the neutrino magnetic momentμν<  2.9×10−11μBat 90% C.L. is derived from the data processing.

DANSS is a highly segmented 1 m 3 plastic scintillator detector. Its 2500 one meter long scintillator strips have a Gdloaded reflective cover. The DANSS detector is placed under an industrial 3.1 GW th reactor of the Kalinin Nuclear Power Plant 350 km NW from Moscow. The distance to the core is varied on-line from 10.7 m to 12.7 m. The reactor building provides about 50 m water-equivalent shielding against the cosmic background. DANSS detects almost 5000 ν e per day at the closest position with the cosmic background less than 3%. The inverse beta decay process is used to detectν e . Sterile neutrinos are searched for assuming the 4ν model (3 active and 1 sterile ν). The exclusion area in the ∆m 2 14 , sin 2 2θ 14 plane is obtained using a ratio of positron energy spectra collected at different distances. Therefore results do not depend on the shape and normalization of the reactorν e spectrum, as well as on the detector efficiency. Results are based on 966 thousand antineutrino events collected at three different distances from the reactor core. The excluded area covers a wide range of the sterile neutrino parameters up to sin 2 2θ 14 < 0.01 in the most sensitive region.Published in the Phys.Lett.B as

The result of the neutrino magnetic moment (NMM) measurement at the Kalinin Nuclear Power Plant (KNPP) with GEMMA spectrometer is presented. The antineutrinoÄelectron scattering is investigated. A high-purity germanium (HPGe) detector with a mass of 1.5 kg placed at a distance of 13.9 m from the 3 GW th reactor core is exposed to the antineutrino ux of 2.7 • 10 13 cm −2 • s −1. The recoil electron spectra taken in 18134 and 4487 h for the reactor ON and OFF periods are compared. The upper limit for the NMM μν < 2.9 • 10 −11 μB at 90% C.L. is derived from the data processing.

The νGeN is new experiment at the Kalinin Nuclear Power Plant (KNPP) for detection of coherent Neutrino-Ge Nucleus elastic scattering. Recent neutrino and Dark Matter search experiments have revolutionized the detection of rear events, and rear events with low energies, in particular. Experiments have achieved sensitivities on the level of several events per hundred kg of detector material per day with energy thresholds from few hundred eV. This opens up a new unique possibility for experimental detection of neutrino-nucleus coherent scattering that has been considered to be impossible so far. The νGeN project uses low threshold high-purity Ge-detectors (HPGe) developed by JINR (Dubna, Russia) in collaboration with BSI (Baltic Scientific Instruments, Riga, Latvia) for creation of a setup designated for first observation of neutrino coherent scattering on Ge. As a powerful neutrino source the experiment will use electron antineutrinos from one of the power-generating units (reactor unit #3) of the KNPP. The coherent neutrino scattering will be observed using a differential method that compares 1) the spectra measured at the reactor operation and shut-down periods; 2) the spectra measured at different distances from the reactor core during the reactor operation. For a setup placed at a 10 m distance from the center of reactor core and with an energy threshold of 350 eV up to tens of events corresponding to neutrino coherent scattering on Ge are expected to be detected per day in the constructed setup with four HPGe low-energythreshold detectors (∼400 grams each). The setup sensitivity will be even more increased by using new detectors with total mass up to 5 kg.

The result of the 3-year neutrino magnetic moment measurement at the Kalinin Nuclear Power Plant (KNPP) with the GEMMA spectrometer is presented. Antineutrino-electron scattering is investigated. A high-purity germanium detector of 1.5 kg placed at a distance of 13.9 m from the 3 GW th reactor core is used in the spectrometer. The antineutrino flux is 2.7×10 13ν e/cm 2 /s. The differential method is used to extract ν-e electromagnetic scattering events. The scattered electron spectra taken in 5184+6798 and 1853+1021 hours for the reactor ON and OFF periods are compared. The upper limit for the neutrino magnetic moment µν <3.2×10 −11 µB at 90% CL is derived from the data processing.