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 15 N(p, γ ) 16 O reaction provides a path from the CN cycle to the CNO bi-cycle and CNO tri-cycle. The measured astrophysical factor for this reaction is dominated by resonant capture through two strong 16 O reaction. The results indicate that the direct capture contribution was previously overestimated. We find the astrophysical factor to be S(0) = 36.0 ± 6.0 keV b, which is about a factor of 2 lower than the presently accepted value. We conclude that for every 2200 ± 300 cycles of the main CN cycle one CN catalyst is lost due to this reaction.

The14 C(n, γ) 15 C reaction plays an important role in inhomogeneous big bang models. In [N. K. Timofeyuk et al., Phys. Rev. Lett. 96, 162501 (2006)] it was shown that the 14 C(n, γ) 15 C radiative capture at astrophysically relevant energies is peripheral reaction, i.e. the overall normalization of its cross section is determined by the asymptotic normalization coefficient (ANC) for 15 C → 14 C+n. Here we present new measurements of the 14 C(d, p) 15 C differential cross sections at deuteron incident energy of 17.06 MeV and the analysis to determine the ANCs for neutron removal from the ground and first excited states of 15 C. The results are compared with the previous estimations.

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