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Attempts were made to detect optical bursts from the gamma-ray burst source GBS 0526-66 during Dec. 31, 1984 to Jan. 2, 1985 and Feb. 23 to Feb. 24, 1985, using the one meter reflector of the Kavalur Observatory. Jan. 1, 1985 coincided with the zero phase of the predicted 164 day period of burst activity from the source (Rothschild and Lingenfelter, 1984). A new optical burst photon counting system with adjustable trigger threshold was used in parallel with a high speed photometer for the observations. The best time resolution was 1 ms and maximum count rate capability was 255,000 counts s(-1). Details of the instrumentation and observational results are presented.

Data was obtained from instrumentation on Explorers 34 and 41 on cosmic-ray anisotropy and magnetic field vectors during five solar flare events. The analysis was conducted in the energy range from 0.7 to 7.6 MeV, of the late decay phase, to evaluate the dependence of net cosmic-ray anisotropy vector amplitude and direction on the magnetic field azimuth. Results showed that in the late decay phase the direction of the net cosmic-ray anisotropy vector was invariant in relation to the direction of the magnetic field, particle energy, and species. Within the statistical error of the available data the invariant direction was perpendicular to the mean magnetic field direction.

A determination of the radial gradient for alpha particles (31-46 MeV/nuc) and protons with energies above 7.5 MeV and 44-77 MeV in the region 1.0-0.81 AU is presented for the solar-quiet year 1966. The determinations are based on data from the Pioneer 6 space probe. Two different detectors are used: the Deep River neutron monitor and measurements of low energy protons made on the IMP-C satellite. The average energy response of the Deep River monitor is 16 GeV, whereas the IMP-C data is for protons with energies above 50 MeV. The resulting radial gradient is found to be nearly zero for the alpha particles and slightly negative for the protons. The same qualitative results were found using the IMP-C data and the Deep River neutron monitor to measure the temporal variation in the cosmic ray intensity. The present analysis indicates that detectors over a wide range of energies are suitable for measuring the radial gradient, providing sufficient statistical precision is obtained to evaluate short-term modulation and the azimuthal separation of the detectors is not great.

Impulsive increases in the low energy proton flux observed by the Explorer 34 satellite, in very close time association with geomagnetic storm sudden commencements are described. It is shown that these events are of short duration (20-30 min) and occur only during the decay phase of a solar cosmic-ray flare event. The differential energy spectrum and the angular distribution of the direction of arrival of the particles are discussed. Two similar increases observed far away from the earth by the Pioneer 7 and 8 deep-space probes are also presented. These impulsive increases are compared with Energetic Storm Particle events and their similarities and differences are discussed. A model is suggested to explain these increases, based on the sweeping and trapping of low energy cosmic rays of solar origin by the advancing shock front responsible for the sudden commencement detected on the earth.

Solar low energy cosmic ray population anisotropy from satellite observations during flare event, describing rise time, decay, field alignment and time constant

Anomalous distribution in heliocentric longitude of solar injected cosmic radiation, suggesting interplanetary magnetic field lines of force stochastic wandering

Solar flare radiation data from Pioneer spacecraft, detailing anisotropy, heliocentric longitude gradients, decay time constants and energy spectra

Anisotropy of solar cosmic ray electrons, considering parallel diffusion coefficients for ions and electrons

Satellite-borne anisotropy and energy spectra measurement instruments for cosmic ray electrons and protons and solar and galactic X-rays

Solar cosmic ray phenomena, noting ionospheric effects and physical processes near sun

Solar flare event of 28 January 1967, observing parent flare location, particle fluxes and diffusion and spectral exponent

High energy solar flare data from neutron monitor stations supplemented by low energy data from interplanetary space probes Pioneer 6 and 7

Time dependence, anisotropy and spectral composition of cosmic radiation generated during series of flares during July 5-20, 1966 by Pioneer 6 observations

Solar cosmic ray anisotropy measurement by Explorer 34 satellite during solar flare events

Cosmic ray anisotropy direction during solar proton events compared with concurrent interplanetary magnetic field vector direction, using Pioneer 6 data

Enhanced fluxes of energetic particles coincident with onset of solar flare initiated Forbush decrease cause particle acceleration in shock wave

Flare initiated and corotating Forbush decreases from Pioneer 6 and 7 deep space probes

Asymptotic directions of cosmic ray particles calculation with tabulated results for 79 points on earth surface

Inter relationship of cosmic ray anisotropies and interplanetary magnetic field

Time dependency, anisotropy, propagation and spectral properties of cosmic radiation released by solar flares during sunspot activity

Cosmic ray propagation processes studied from measurement of anisotropic character of cosmic radiation /1965-1966

Intense fluxes of charged particles associated with disturbances in interplanetary medium during 1966

Time dependency, anisotropy degree and spectral composition of cosmic radiation generated during July 1966 solar flares as observed by Pioneer VI

Recurrent cosmic-ray modulation phenomena with Forbush decrease characteristics correlated with M-region magnetic storms, concluding that each series results from shock wave solar initiated

Anisotropic cosmic radiation with flare effects flowing out of Sun and along filamentary magnetic structures imbedded in solar wind

Cosmic ray flare effects observed by Pioneer VI SPACECRAFT

Semidiurnal anisotropy of cosmic radiation observed from neutron monitor data treated by numerical filter techniques

Cosmic ray intensity measured by Mariner III AND by ground neutron monitors during Forbush decrease

Cosmic ray intensity and flux and velocity of solar wind measured by Mariner II and ground neutron monitors during Forbush decrease

Cosmic ray deflections in geomagnetic field, variational coefficients, and diurnal intensity variations - tables

Investigation of semidiurnal anisotropy of cosmic radiation using data from neutron monitors

Plasma velocity correlation with various indices of solar, cosmic ray and terrestrial activity measured during several solar rotations, using Mariner II spacecraft

Correlation of plasma velocity with indices of solar and terrestrial activity - cosmic radiation

Detailed particle observations from various Pioneer spacecraft located at different heliolongitudes during the complex solar flare events of Mar. 30 to Apr. 10, 1969, have been utilized to investigate the energy dependence of azimuthal gradients of cosmic ray particles and its effect on the decay of the flare intensity. For an observer located to the east of the centroid of the population, the azimuthal corotation term and the convection term will be additive, resulting in a short decay time constant. An observer located to the west of the centroid of the population will experience a much longer decay time constant, the corotation term partially or completely compensating the loss of particles due to convection. At very low energies, the azimuthal corotation term may even be more than the convection term, thus resulting in a rise in intensity instead of decay during the later part of the event.