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The Spin Physics Detector, a universal facility for studying the nucleon spin structure and other spin-related phenomena with polarized proton and deuteron beams, is proposed to be placed in one of the two interaction points of the NICA collider that is under construction at the Joint Institute for Nuclear Research (Dubna, Russia). At the heart of the project there is huge experience with polarized beams at JINR. The main objective of the proposed experiment is the comprehensive study of the unpolarized and polarized gluon content of the nucleon. Spin measurements at the Spin Physics Detector at the NICA collider have bright perspectives to make a unique contribution and challenge our understanding of the spin structure of the nucleon. In this document the Conceptual Design of the Spin Physics Detector is presented.

Modernized version of the combined opto-acoustical gravitational wave detector OGRAN is presented. Located in the deep underground of the Baksan Neutrino Observatory this setup is aimed to work on the program of collapsing stars searching for in multi-channel manner with the neutrino telescope BUST. The both instruments have the sensitivity allowing a registration of collapses in our Galaxy as rare events with the estimated probability 0:03 year-1. The OGRAN narrow band sensitivity at the kilohertz frequency is limited by its acoustical mode thermal noise achieving 10^{-20} in term of metric perturbations. A possible algorithm of the joint data analysis for the both instruments is developed and resulting formulae of the right detection probability are given. A future increasing of the OGRAN sensitivity associated with the moderate cooling (nitrogen temperature) of the acoustical mode is also discussed., Comment: 15 pages, 4 figures, for Proceedings of 10th Freedman Seminar Conference, accepted for publication in IJMP_A

For the fermion transformation in the space all books of quantum mechanics propose to use the unitary operator $\widehat{U}_{\vec n}(\varphi)=\exp{(-i\frac\varphi2(\widehat\sigma\cdot\vec n))}$, where $\varphi$ is angle of rotation around the axis $\vec{n}$. But this operator turns the spin in inverse direction presenting the rotation to the left. The error of defining of $\widehat{U}_{\vec n}(\varphi)$ action is caused because the spin supposed as simple vector which is independent from $\widehat\sigma$-operator a priori. In this work it is shown that each fermion marked by number $i$ has own Pauli-vector $\widehat\sigma_i$ and both of them change together. If we suppose the global $\widehat\sigma$-operator and using the Bloch Sphere approach define for all fermions the common quantization axis $z$ the spin transformation will be the same: the right hand rotation around the axis $\vec{n}$ is performed by the operator $\widehat{U}^+_{\vec n}(\varphi)=\exp{(+i\frac\varphi2(\widehat\sigma\cdot\vec n))}$., Comment: New version in English

It is considered the problem of spin physics related with the difference of representation of the elastic interaction between the neutron and proton. In the first case the charge-exchange reaction $np\to pn$ under the angle $\theta$ is supposed, in the second --- the simple elastic scattering of $np\to np$, when the neutron is going in opposite direction $\pi-\theta$. The transition from one representation to another is provided by the Majorana operator. In the framework of impulse approximation it is twice calculated the quasi-elastic charge-exchange reaction of a neutron on a deuteron. In the frame of $nd\to p(nn)$ scattering of proton to the angle $\theta$ it gives the well-known Dean formula. Using other representation $nd\to (nn)p$ as a neutron elastic scattering under the angle $\pi-\theta$ (together with neutron-spectator in $nn$-pair) the alternative formula is presented., Comment: English

The reaction nd -> p(nn) produce two slow neutrons in the final state instead of deuteron. In the first view we can take into account the binding energy e ~ 2.23 MeV but this approach can not explain all features which are observed in the momentum spectrum of the secondaries protons. We need to suppose that two slow neutrons in the final state form the intermediate system which has own distribution of internal Fermi momentum., Comment: in Russian

Enhancing of sensitivity of the opto-acoustical gravitational wave (GW) antenna OGRAN installed in the underground facilities of Baksan Neutrino Observatory is analyzed. Calculations are presented showing a sensitivity improving on two orders of value after a cooling the solid body acoustical part of the antenna to the nitrogen temperature. A possibility of keeping of the same optical scheme of the antenna at low temperature is discussed. Design of modernized construction for cryogenic version of the antenna OGRAN is described. Test experiments with cooled pilot model carrying cryogenic mirrors illuminated by the optical pump up to 0.5 W are presented., Comment: 9 pages, 5 figures

Application of the large scale gravitational wave interferometers for measurement of geophysical signals at very low frequencies is considered. Analysis is concentrated on the mechanism of penetration of quasistatic geophysical perturbation through the main interferometer output. It is shown that it has a parametrical nature resulted in slow variations of the optical transfer function of the interferometer. Geophysical modulation index is calculated for any harmonical component of the output spectrum, but mainly for a photon circulation frequency appeared in the case of stochastic illumination of modes neighbour to the central resonance. Value of the effect is estimated for different operational regimes of the device. For improvement of geophysical signal readout a modernization of the instrument with using of two component resonance optical pump is proposed and a correspondent calculation is carried out. Numerical estimations for different regimes of the setup are given together with discussion of possible application for measuring some weak gravitational effects., Comment: 29 pages, 1 figure, submitted to Classical and Quantum Gravity