Measurements obtained at Deep River, Canada, from two large neutron monitors, and at Cambridge, Massachusetts, from a high counting rate meson monitor, during the solar cosmic-ray injections of November 12 and 15, 1960, are reported. In addition, rate-meter pen traces of the neutron increases and a magnetometer trace of H, obtained at Deep River, are reproduced. The solar cosmic-ray increase of November 12 appears to be unique in that while it was in progress a sharp Forbush decrease happened to occur as shown by the MIT meson intensity. Half an hour before the onset of the Forbush decrease, and coincident with a conspicuous increase of H, the intensity of the solar cosmic radiation doubled and then exhibited strong rapid oscillations. We advance arguments that the changes of intensity of the solar cosmic ray• observed at high latitudes at the time of the magnetic disturbance and Forbush decrease are due to the earth sampling solar cosmic rays trapped in the gas cloud responsible for these latter effects. The events of November 12 and 15 are both shown to be in agreement with a recent model for the magnetic fields in the inner solar system. At the time of the solar cosmic-ray increase of November 15, the earth was already inside a trapping region, and periodic oscillations of the solar cosmic-ray intensity were observed lasting for about 2 hours. It is suggested that these oscillations may be closely connected with the storage mechanism. 1363 1364 STELJES, CARMICHAEL, AND McCRACKEN over an hour to reach the same fraction of its initial maximum intensity. A r•markable succession of fluctuations of the solar cosmic rays of periodicity about 20 minutes, lasting for slightly more than 1 hour after the beginning of the November 15 increase, was observed at Deep River. In view of these interesting features it seems worth while to describe and discuss the observations without waiting for data from other cosmicray stations. It has recently been shown [McCracken and Palmetra, 1960; Obayashi and Hakura, 1960] that previously observed solar flare cosmic-ray effects are in agreement with a simple model for the magnetic fields in the inner solar system. We shall present the experimental data from both Deep River and MIT and show that the same model provides a good explanation of the November events as observed at our laboratories. We shall not, in this paper, try to apply any further tests of the model requiring detailed data from elsewhere in the world, but we shall make some general predictions of what may have been observed elsewhere. We shall also describe the newly observed fast fluctuations in detail and discuss their possible significance. The model is the one originally suggested by Cocconi, Gretsch, Morrison, Gold, and Hayakawa [1958] at Varenna in 1957. This model has since then been strongly advocated by Gold [1959], for example, at the 1959 'Symposium on the Exploration of Space.' INSTRUMENTS Deep River Laboratory. The Deep River Laboratory is 145 m above sea level at 46.10øN. Lat. and 77.50øW. Long. The geomagnet...

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A 3-NM-64 neutron monitor and a 2-MT-64 muon monitor were operated overland at 44 sites near sea level and on mountains in Canada, the USA, and Mexico in April, May, and June, 1965, when the intensity of cosmic radiation attained its 11-year maximum. The equipment is briefly described and the original results of the measurements are listed. Some necessary corrections for instrumental effects are discussed. The corrections made to eliminate the secular variations of the cosnlic radiation and the dependence upon temperature structure of the atmosphere are given in detail. This paper is the first of a set of five dealing with latitude surveys made in 1965 and 1966. Reduction of the observations to a common pressure level is carried out in the final paper of the set.

We have studied in detail the correlation between the 24 hr average anisotropy of galactic cosmic rays as measured by a ring of high latitude neutron monitors and the direction of the 24 hr average interplanetary magnetic field. From the two year data period 1967-68, we have selected events showing instances of marked non-equilibrium anisotropy (i.e. large departures from the average 'corotational' anisotropy). These include trains of spontaneously arising enhanced diurnal variation as well as Forbush decrease events showing large anisotropy in the pre-decrease, main or recovery phase. We find that the observed anisotropies are well fitted by the assumption that the streaming of galactic cosmic rays is composed of two components (1) radial streaming away from the Sun with a velocity of ~ 400 km/s and (2) diffusive streaming along the direction of the interplanetary magnetic field. The diffusive streaming is mostly towards the Sun. This description is also applicable to periods characteristic of the quiet time diurnal anisotropy. These results are analogous to those obtained by McCracken, Rao and Ness for 7-45 MeV solar flare particles.