view Abstract Citations (28) References (36) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Measurement of the cosmic-ray sidereal anisotropy near 1500 GV Cutler, D. J. ; Bergeson, H. E. ; Davies, J. F. ; Groom, D. E. Abstract A large underground muon detector has operated at an average rate of 4.47 Hz for most of a 2.7-year interval, starting on Jan. 1, 1978, in a search for periodic variations in the cosmic-ray flux at a median rigidity of 1.5 x 10 to the 12th V. A peak with relative amplitude of 4.1 +1.2, -0.9 x 10 to the -4th is observed in the Fourier transform of data at the sidereal frequency, where the errors are 68% confidence limits based on an off-center Rayleigh distribution. After correction for solar motion, the projected anisotropy is 6.4 +1.2, -1.0 x 10 to the -4th at the right ascension of 3.8 + or - 0.7 h. Also observed are a second sidereal harmonic, with an amplitude of 2.8 +0.9, -0.7 x 10 to the -4th at the ascension 7.8 + or - 1.0 h and a third harmonic of amplitude 2.3 +1.0, -0.7 x 10 to the -4th at 7.8 + or - 1.4 h ascension. There is no discernible peak at the antisidereal frequency, and the small amplitude at the solar frequency implies an upper atmosphere diurnal temperature amplitude of less than about 0.1 C. Publication: The Astrophysical Journal Pub Date: September 1981 DOI: 10.1086/159246 Bibcode: 1981ApJ...248.1166C Keywords: Anisotropic Media; Cosmic Rays; Muons; Particle Flux Density; Sidereal Time; Energy Spectra; Fourier Transformation; Frequency Response; Periodic Variations; Radiation Measurement; Space Radiation full text sources ADS |