Application of stochastic resonance in gravitational-wave interferometer
We investigate a novel approach which improves the sensitivity of a gravitational-wave interferometer due to the phenomenon of stochastic resonance (SR), performing in a nonlinear cavity (NC). The NC is installed at the output of the interferometer before the photodetector so that the optical signal emerging from the interferometer passes through the NC. Under appropriate circumstances, a specific transformation of the noisy signal inside the NC takes place, which results in the increase of the output signal-to-noise ratio (SNR). As a result, the noisy optical signal of the interferometer becomes less noisy after passing through the NC. The improvement of SNR is especially effective in the bistable NC for wideband (several hundred Hz) detection, when the chirp gravitational-wave signal is detected. Then, for an input SNR of $\ensuremath{\sim}0.05$, the output SNR can be increased up to $\ensuremath{\sim}0.5$. When the detection bandwidth is narrowed, the SR mechanism gradually fades out, and the SNR gain tends to 1. The SNR gain also tends to 1 when the NC is transformed to a linear cavity. Proposed enhancement of the SNR due to SR is not dependent on noise type, which dominates in the interferometer. Particularly, the proposed approach is capable of increasing the SNR at a given amplitude of displacement noise.

title: Advanced configuration of gravitational-wave interferometer on the base of “sensitive mode” in “white-light cavity”
abstract: A novel conception of “sensitive mode” (SM) is proposed to apply in gravitational-wave advanced interferometer configuration (AIC). The SM is resonant oscillation of electromagnetic field in “white-light cavity”, where the resonance line is broadened without decreasing cavity quality. The resonant field frequency of the SM is greatly susceptible to the change of cavity length, and the SM is established in a cavity with time constant smaller than a conventional mode. Due to these advantages the sensitivity and bandwidth of AIC can be increased.

title: Investigation of cosmic ray anisotropy based on Tsumeb neutron monitor data
abstract: We investigate sidereal daily variations of galactic cosmic rays (CR) by using Tsumeb neutron monitor’s (NM) hourly count during 1977–2000. For that purpose a special data analysis is applied to remove solar induced daily variations and improve sidereal variations. Then, the declination of protons in the Earth’s magnetosphere is analyzed for the proper determination of particles’ asymptotic directions. As a result we found ∼0.07% anisotropy with an excess flux from the direction of the right ascension (RA) ∼6 h. The reversal of solar magnetic field from the negative polarity state (in the time interval 1977–1989) to the positive state (in the interval 1990–2000) does not decrease the amplitude of anisotropy, which means that the origin of anisotropy found is “heliospheric” and not “galactic”. We conclude that the observed anisotropy is a tail-in anisotropy , which has been discovered earlier for higher energy (150 GeV–10 TeV) particles in several experiments with underground muon monitors and air-shower detectors. It is believed that the tail-in anisotropy is caused by heliotail boundary, located in the direction RA ∼6 h, where the interaction between galactic and solar magnetic fields produces CR acceleration

title: Microwave gyroscope-novel rotation sensor
abstract: High performance microwave gyroscope (MG) is theoretically developed for the first time to our knowledge. MG is based on Sagnac effect in microwave ring resonator (RR), where a specially taylored phase shifter (PS) on the basis of surface acoustic waves is inserted. Due to that beat frequency becomes proportional to square (or cubic) root upon rotation rate and therefore hugely increases. In the result MG has few order higher sensitivity and dynamic range than state-of-the-art laser gyros, so it can serve as an advanced rotation sensor in navigation and fundamental sciences.

title: Detection of high energy solar protons during ground level enhancements
abstract: Registration of high energy solar protons by middle and low latitude particle monitors during ground level enhancements (GLE) is investigated. We have developed a comprehensive method, for revealing weak GLE signals. The main result of the method is estimation of probability of error for given value of observed signal amplitude. We derived, that for middle energy protons, the 99% confidence limit of GLE signal detection is determined by ∼4.3 σ of observed signal, whereas for highest energy protons it is determined by ∼3.7 σ . Applying this method to GLE-65 at 28 October 2003, GLE-69 at 20 January 2005 and GLE-70 at 13 December 2006, we make conclusions about the maximal energy of protons during these events. We claim on the presence of >20…30 GeV protons in GLE-65 with the probability of error ∼7% and in the GLE-69 with the probability of error ∼0.4%. However, during GLE-70 maximal energy of protons was ∼10 GeV.

title: Statistical methods for signal estimation of point sources of cosmic rays
abstract: The estimation of the significance of the peaks in one- and two-dimensional distributions is one of the most important problems in high-energy physics and astrophysics. The physical inference from low-statistics experiments usually is biased and many discoveries lack further confirmation. One of the typical mistakes in physical inference is the use of non-adequate statistical models. We analyze the significance of the experimental evidence in the on-going efforts of detecting the point source of cosmic rays. We found that simple statistical models (Gaussian or Poisson) did not adequately describe the experimental situation of point source searches. To avoid drawbacks related to usage of the incorrect statistical model, we introduce new extremum statistical models appropriate for the point source searches. The analysis is conducted in the framework of two models utilizing extremum statistics: first – using the fixed grid of celestial coordinates, and second – using the tuned grid (introducing more degrees of freedom in the search). The test distributions for the significance estimation are obtained both from simulation models and from the analytical model of extremum statistics. We show that the second model gives adequate physical inference, while the first model can lead to the positively biased conclusions of the point source significance.

title: The analysis of proton- and deuteron-induced-reaction cross sections on tin isotopes at the beam energy of 3.65 GeV/nucleon
abstract: The total inelastic cross sections of the reactions of protons and deuterons on nuclear targets of enriched tin isotopes are compared. The factorization of cross sections of reactions is discussed. Furthermore, the comparison of theoretical estimations on total inelastic cross sections with corresponding experimental ones is made.

title: Fission of pre-actinide nuclei
abstract: A study of photofission on 181Ta nucleus induced by bremsstrahlung photons with endpoint energies of 50 and 3500 MeV has been performed. The fission yields have been measured by using the induced-activity method in an off-line analysis. The absolute photofission cross sections for the tantalum target at 50 and 3500 MeV are found to be 5.4 \pm 1.1 microb and 0.77\pm0.11 mb, respectively, and the corresponding deduced fissilities are (0.23\pm0.05) x 10^{-3} and (2.9 \pm 0.9) x 10^{-3}. Mass- and charge-yield distributions were derived from the data. The results were compared with the simulated results from CRISP code for multi-modal fission by assuming symmetrical fission mode.

title: Recoil properties of fragments formed in 4.4 GeV deuteron-induced reactions on a gold target
abstract: The recoil properties of fragments produced by the interaction of 4.4 GeV deuterons with a ${}^{197}$Au target have been studied. New experimental data on recoil properties for 90 nuclei, varying from ${}^{24}$Na to ${}^{198}$Au, were obtained. The technique applied was the thick-target thick-catcher and induced activity method. The deuteron beam was obtained from the Nuclotron of the Laboratory of High Energies (LHE), Joint Institute for Nuclear Research (JINR), Dubna. The experimental data were analyzed on the basis of the standard two-step vector model formalism. From the analysis of the reaction investigated here, we could find evidence that the cooling process of excited nuclei can be due to the coexistence of different decay modes such as evaporation, fission, and (multi)fragmentation. Fission and multifragmentation can contribute appreciably to the formation of products in the intermediate mass range. The kinematic characteristics of residual nuclei formed in the present deuteron-induced reaction have been compared to those from proton-induced reactions with gold target.