Astronomy and Astrophysics – Astrophysics
Scientific paper
Apr 1999
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1999jgr...104.6737h&link_type=abstract
Journal of Geophysical Research, Volume 104, Issue A4, p. 6737-6750
Astronomy and Astrophysics
Astrophysics
20
Solar Physics, Astrophysics, And Astronomy
Scientific paper
We have analyzed the yearly averaged sidereal daily variations in the count rates of 46 underground muon telescopes by fitting Gaussian functions to the data. These functions represent the loss cone and tail-in anisotropies of the sidereal anisotropies model proposed by Nagashima et al. [1995a, b]. The underground muon telescopes cover the median rigidity range 143-1400 GV and the viewing latitude range 73°N-76°S. From the Gaussian amplitudes and positions we have confirmed that the tail-in anisotropy is more prominent in the southern hemisphere with its reference axis located at declination (δ)~14°S and right ascension (α)~4.7 sidereal hours. The tail-in anisotropy is asymmetric about its reference axis, and the observed time of maximum intensity depends on the viewing latitude of the underground muon telescopes. We also find that the declination of the reference axis may be related to the rigidity of the cosmic rays. We show that the loss cone anisotropy is symmetric and has a reference axis located on the celestial equator (δ~0°) and α~13 sidereal hours. We have used the parameters of the Gaussian fits to devise an empirical model of the sidereal anisotropies. The model implies that the above characteristics of the anisotropies can explain the observed north-south asymmetry in the amplitude of the sidereal diurnal variation. Furthermore, we find that the anisotropies should cause the phase of the sidereal semidiurnal variation of cosmic rays to be observed at later times from the northern hemisphere compared to observations from the southern hemisphere. We present these results and discuss them in relation to current models of the heliosphere.
Akahane Shigenobu
Duldig Marc L.
Fenton A. G.
Fenton K. B.
Fujii Zenjiro
No associations
LandOfFree
Gaussian analysis of two hemisphere observations of galactic cosmic ray sidereal anisotropies does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Gaussian analysis of two hemisphere observations of galactic cosmic ray sidereal anisotropies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Gaussian analysis of two hemisphere observations of galactic cosmic ray sidereal anisotropies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-891082