Measurements of relativistic electrons (500keV to 12MeV) within the drift loss cone during geomagnetic storms in the spring of 1994, obtained with MKL instrument aboard the low-altitude (∼500km) polar-orbiting satellite, CORONAS-I, are reviewed. CORONAS-I satellite observed two more pronounced electron enhancements during the period studied (March–April 1994). Time profile of Dst index indicates that these events occurred after magnetic storms on March 6–8, 1994 (Dst=−109nT) and April 2–4, 1994 (Dst=−111nT). Both time and L shell variations of the precipitating electron fluxes over the wide L shell range of 1–9 are presented and discussed. On the average, these fluxes had a maximum value at L=3.8–4.6 observed during the storm recovery phases.

The InterSONG instrument now being developed at the Skobel’tsyn Institute of Nuclear Physics will allow the sensitivity of experiments on solar neutrons to be significantly raised by performing measurements in the immediate neighborhood of the Sun. It is expected that this instrument will be used on the Inter-HELIOS automatic interplanetary station operating at distances of as many as 25 solar radii. The instrument is based on a LiI scintillating crystal enriched with 6 Li, and a boron-containing plastic scintillator that also acts as a fast neutron moderator. The instrument is designed to detect neutrons with energies of 0.1–100 MeV and electromagnetic radiation over the range 0.03–10 MeV.

Neutron measurement results obtained at SINP MSU since 1970 are presented. These measurements were made using techniques based on neutron moderation and subsequent detection in a Li6I(Eu) crystal or a He3 coronal counter. The measurements were mainly carried out in orbits with inclination of 52° and altitudes of 200–450km. The spatial and angular distributions of the measured neutron fluxes were studied. The albedo neutron flux was estimated according to the count rate difference for opposite detector orientations towards Earth and away from it. This flux is comparable to the local neutron flux outside the Brazil anomaly region, where local neutrons dominate. Neutron fluxes, generated by solar protons, were detected during a solar flare on June 6, 1991 for the first time. Their spectrum was estimated as a power law with α>2.

According to the data from the SONG instrument on board the low altitude high inclination CORONAS-I satellite, the fluxes of gamma rays with energies between 120 keV and 8.3 MeV are reviewed. The observations were made during the interval from May 1994 to early July 1994. Comparison with energetic electron fluxes obtained from AE-8 model is done, and thus the gamma-ray production mechanism is discussed. Available data are used to investigate the fine spatial structure in the Brazilian anomaly, as well as to analyse outer zone of bremsstrahlung electrons. To do this, the L-B maps are constructed and energy spectral characteristics of gamma-ray fluxes are investigated.

A scintillation spectrometer based on a combination of CsI(Tl) and NaI(Tl) crystals was developed. The instrument ensures a reliable separation of X rays, γ rays, and neutrons by the difference in their signal shapes in an energy range of 0.03–30 MeV. The mean time of signal processing is 4 μs.

The SONG instrument on board CORONAS-I satellite (fluxes of protons E p >70 MeV and electrons E e >55 MeV ) observed the effects of the Forbush effects caused by interplanetary magnetic field sector boundary crossing and coronal mass ejection in April 1994. The latitudinal dependence of these effects is analyzed and compared with data from ground-based neutron monitors at different latitudes. It was found that while measurements by SONG instrument over the polar caps were in good agreement with the data of the neutron monitor at polar latitudes, at the middle latitudes during the Dst decreases, the cut-off rigidity variations were probably so strong that instead of the usual short-time decrease the SONG instrument detected a significant enhancement of particle fluxes. The influence of interplanetary medium conditions on the cosmic ray flux is analyzed and discussed.

A low altitude satellite with polar orbit, namely CORONAS-F has been launched on July 31, 2001. We briefly list the possibilities of a complex instrument SKL, and on the basis of similar measurements by CORONAS-I we illustrate the possible tasks for magnetospheric studies. Such orbit allows to sample with relatively high time resolution the projection series of various magnetospheric regions to low altitudes and to indicate changes within.

For heliospheric instrumentation we propose to discuss spectrometer of neutrons with energies 0.05-5 MeV. LiI(Eu) crystal 4*3 cm enriched in Li-6, surrounded by a plastic scintillator 1-3 cm thick loaded with B-10 is used as a detector. Neutrons will undergo elastic scattering with the hydrogen in the plastic. A delayed coincidence within a window of 0.1 - 10 mus in either scintillator is a signature of a neutron, with the initial fast plastic signal pulse height being a direct measure of the incident neutron's energy. A fast charged particle will be vetoed as simultaneous signals in both scintillators. Gamma's with energies 0.03-10 MeV will be identified too as signals in LiI alone. Calculated effective area for normal neutron incidence is 0.3-5.6 cm(2). Estimated effective area for gamma detection is 3-12 cm(2). Mass of the instrument is <1.5 kg. Power of the detector is about 1.5 watt, needing telemetry - 40 b/s.

The energetic charged particles (Ep > 70 MeV and Ee> 55 MeV) were measured by SONG instrument on board low altitude polar-orbiting CORONAS-I satellite. The interplanetary shock arrivals on 3-4 April 1994 (Dst=111 nT) and 17 April 1994 (Dst=-201 nT) caused significant variations of fluxes of the energetic charged particles detectable on altitude of CORONAS-I satellite. The latitudinal dependence of these effects has been investigated separately for south and north of the minimum L equator on 500 km. The comparison with changes in the cutoff rigidities calculated by Smart et al. (1999a) is done.

Recent investigations have shown that radiation dose onboard orbital station MIR under a shield of some tens g/cm is mostly defined by fluxes of neutrons due to interactions with the matter of the station of protons of cosmic rays and of inner radiation belt. As secondary neutron fluxes are dependent on spacecraft mass onboard International Space Station (ISS) these fluxes compared with MIR-station can be yet more. In this paper we present results of the simulations of the flux and energy spectrum of secondary neutrons out of Earth s radiation belts for main laboratories and modules of ISS for its full configuration. Calculations were made both in the energy ranges ¡10 MeV and ¿10 MeV for maximum and minimum of solar activity. To test accuracy of the estimations the same simulations are made for orbital station MIR and CORONAS-I satellite. Obtained for MIR-station and CORONAS-I results are compared with measured values. Correspondence to: S. Ryumin (ryumin@srdlan.npi.msu.su)

Results of the statistical study of gamma ray fluxes in the energy channels 0.12 - 0.32 MeV, 3.0 - 8.3 MeV,measured by the instrument SONG on board the low altitude high inclination satellite CORONAS-I are presented. The geographic maps based on sets of data in March June 1994 are constructed as well as latitudinal distribution (i.e. the variation of average fluxes with vertical cut - off rigidity) for higher energies is given. The irregular spatial structures of gamma ray flux increases in subauroral zone and at lower latitudes are discussed.