Preparation of the Neutrino-4 experiment on search for sterile neutrino and the obtained results of measurements

The experiment Neutrino-4 had started in 2014 with a detector model and then was continued with a full-scale detector. All steps of preparatory work on this experiment are presented. Were obtained the results of measurements of reactor antineutrino flux and spectrum dependence on the distance in the range 6-12 meters from the center of the reactor core at SM-3 reactor (Dimitrovgrad, Russia). Using all collected data, we performed the model independent analysis on the oscillation parameters $\Delta m_{14}^2$ and $\sin^22\theta_{14}$. The method of coherent summation of results of measurements allows us to directly observe the effect of oscillations. We observed an oscillation effect at CL $2.8\sigma$ in vicinity of $\Delta m_{14}^2 \approx 7.25\pm1.0\text{eV}^2$ and $\sin^22\theta_{14}\approx 0.26\pm0.09(2.8)\sigma$. We provide a comparison of our results with results of other experiments on search for sterile neutrino. Combining the result of the Neutrino-4 experiment and the results of measurements of the gallium anomaly and reactor anomaly we obtained value $\sin^22\theta_{14} \approx 0.19 \pm 0.04 (4.6\sigma)$. Also was performed comparison of Neutrino-4 experimental results with results of other reactor experiments NEOS, DANSS, STEREO, PROSPECT and accelerator experiments MiniBooNE, LSND and results of the IceCube experiment. Mass of sterile neutrino obtained from data collected in the Neutrino-4 experiment (in assumption $m_4^2\approx \Delta m_{14}^2$) is $m_4=2.68\pm0.13\text{eV}$. Using the estimations of mixing angles obtained in other experiments and our new results we can calculate, within 3+1 neutrino model, masses of electron, muon, and tau neutrinos: $m_{\nu_e}^{\text{eff}}=(0.58\pm0.09)\text{eV}, m_{\nu_\mu}^{\text{eff}}=(0.42\pm0.24)\text{eV}, m_{\nu_\tau}^{\text{eff}}\leq 0.65\text{eV}$.