125873936
A Program for investigation of the muon component in EAS on the magnetic spectrometer ANI in the energy range from 5-GeV to 3000-GeV
15765199
About EAS size spectra and primary energy spectra in the knee region
Based on the unified analyses of KASCADE, AKENO, EAS-TOP and ANI EAS size spectra, the approximations of energy spectra of different primary nuclei have been found. Calculations were carried out using SIBYLL and QGSJET interaction models in 0.1-100 PeV primary energy range. The results point to existence of both rigidity-dependent steepening energy spectra at R=200-400 TV and an additional proton (neutron) component with differential energy spectrum (6.1+/-0.7)10^{-11}(E/Ek)^{-1.5} (m^2.s.sr.TeV)^{-1} before the knee Ek=2030+/-130 TeV and with power index g2=-3.1+/-0.05 after the knee.
14618248
Anisotropy analysis of EAS data in the knee region
Based on MAKET-ANI EAS data the distributions of equatorial coordinates of EAS core directions are obtained in the knee region. Anisotropy of primary cosmic rays is displayed only by declination equatorial coordinates (20+/-3 degrees) at primary energies more than 5-10 PeV. The fraction of anisotropic component turns out ~10% in the knee region.
119931073
Primary cosmic ray energy spectrum in terms of the GAMMA muon data
The energy spectrum of the primary cosmic rays is obtained by conversion from the truncated muon size spectrum of EAS studied with the GAMMA array. The previously observed dependence of E 0 on N μ tr at various zenith angles is used. It is shown that the present spectrum has the same structure (“bump”) as the spectrum determined by another independent multi-parametric energy estimation method confirming that the “bump” structure is not produced by uncertainties in our methods.
103336904
Calibration of energy measured in Roentgen emulsion experiments. (In Russian)
117993503
Search Capability for eta ---> nu(e, tau) anti-nu(e, tau) Decays in Cubic Kilometer Neutrino Detectors
We investigate the discovery potential of cubic-kilometer neutrino observatories such as IceCube to set stringent limits on the forbidden decays η → v e v e and η → v τ v τ . The signatures for these decays are cascade events resulting from the charged-current reactions of v e , v τ , v e , and v τ on nuclei in such detectors. Background cascade events are mainly due to v e 's from atmospheric μ, K + , and K 0 S decays and to a lesser extent from atmospheric v μ neutral-current interactions with nuclei. A direct upper limit for the branching ratio η → v e,τ v e,τ of 6.1 × 10 -4 at 90% CL can be achieved.
15515326
Galactic diffuse gamma-ray flux at the energy about 175 TeV
We present an upper limit of galactic diffuse gamma-ray flux, measured with the GAMMA experiment at energy about 175 TeV. The results were obtained using selection of muon poor extensive air showers at mountain level (700 g/cm 2 , Mt. Ara- gats, Armenia) for 5 GeV muon energy threshold. An upper limit for the differential flux at energy E ≃ 175 +25 20 TeV is equal to (5.8 − 7.0) � 10 12 (ergm 2 � ssr) 1 for 95% confidence level 1 .
118459803
Sharp knee phenomenon of primary cosmic ray energy spectrum
Primary energy spectral models are tested in the energy range of 1-200 PeV using standardized extensive air shower responses from BASJE-MAS, Tibet, GAMMA and KASCADE scintillation shower arrays. Results point towards the two-component origin of observed cosmic ray energy spectra in the knee region (GAPS spectral model) consisting of a pulsar component superimposed upon rigidity-dependent power law diffuse galactic flux. The two-component energy spectral model accounts for both the sharp knee shower spectral phenomenon and observed irregularity of all-particle energy spectrum in the region of 50-100 PeV. Alternatively, tested multi-population primary energy spectra predicted by non-linear diffusive shock acceleration (DSA) models describe observed shower spectra in the knee region provided that the cutoff magnetic rigidities of accelerating particles are 6.0+/-0.3 PV and 45+/-2 PV for the first two populations respectively. Both tested spectral models confirm the predominant H-He primary nuclei origin of observed shower spectral knee. The parameters of tested energy spectra are evaluated using solutions of inverse problem on the basis of the corresponding parameterizations of energy spectra for primary H, He, O-like and Fe-like nuclei, standardized shower size spectral responses in the 550-1085 g/cm^2 atmospheric slant depth range and near vertical muon truncated size spectra detected by the GAMMA array.
118825755
Alternative description of particle shower longitudinal profile
An alternative parametrization of the particle shower longitudinal profile is presented. The accuracy of the obtained shower profile description is about 2-3% for the 0-1500 g/cm^2 atmosphere slant depths and primary H, He,... Fe nuclei in the 1 PeV-10 EeV energy range. It is shown that the shape of shower profile depends only on the nucleon energy, whereas the maximum shower size also depends on the energy of the parental nucleus. Results are based on the CORSIKA simulated shower profiles and are presented in comparison with the Gaisser-Hillas parametrization.