The cosmic ray intensity data recorded with TOKYO Neutron Monitoring Station have been investigated on 60 Quiet Days (QD) in a year for studying the higher harmonics of daily variation during solar cycle 21 and 22.It has been observed that inspite of the abrupt change in the amplitude and the phase of the higher harmonics of daily variation in cosmic ray intensity,the amplitude of third harmonic of daily variation on QDs is larger by a factor of two during the period 1983 to 1986,i.e.the declining phase of solar cycle 21,similar to that observed 11-years ago i.e.,declining phase of solar cycle 20,at Tokyo station.Thus,11-year variation in the tri-diurnal anisotropy of cosmic ray intensity is clearly observed at the Tokyo neutron monitoring station.Further,the amplitude of the fourth harmonic of the daily variation on QD during 1987-90 shows an increasing trend continuously in association with phase of fourth harmonic shifting to earlier hours.
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