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The primary scientific goal of the GRIPS mission is to revolutionize our understanding of the early universe using γ -ray bursts. We propose a new generation gamma-ray observatory capable of unprecedented spectroscopy over a wide range of γ -ray energies (200 keV-50 MeV) and of polarimetry (200-1000 keV). The γ -ray sensitivity to nuclear absorption features enables the measurement of column densities as high as 10 28 cm −2 . Secondary goals achievable by this mission include direct measurements of all types of supernova interiors through γ -rays from radioactive decays, nuclear astrophysics with massive stars and novae, and studies of particle acceleration near compact stars, interstellar shocks, and clusters of galaxies.

In this paper we present Prognoz-8 observations of plasma and lowfrequency (2-105 Hz) waves near the high latitude nightside magnetopause. Dense magnetosheath (MS)-like plasma clouds apparently detached from the magnetopause were often encountered by Prognoz-8 in this region inside the magnetosphere. It is found that such MS-like plasma clouds are always associated with strong wave activity at frequencies Q, < o 5 wLH, where Q, is the proton cyclotron frequency, oLH is the lower hybrid (LH) frequency. We examined in detail 5 MS-like plasma clouds observed during 2 inbound satellite passes through the magnetopause and high latitude tail. In one case the bulk velocity in the apparently detached MS plasma cloud is higher than in the nearby MS. More frequently, high energy non-maxwellian tails or high energy cold ion beams are observed in the cloud or just outside it. Also, we have found that some characteristics of plasma, magnetic field and plasma waves in the reported phenomena are similar to those in the flux transfer events (FTE's) observed on the dayside. Simultaneous observations of FTE's with signatures of plasma acceleration (most probably being a result of magnetic field line reconnection) and intense LH waves is interpreted in the frame of theory predicting that the lower hybrid drift instability is the source of anomalous resistivity in reconnection.* This paper was contributed to the 6th International Symposium on Solar Terrestrial Physics, held in Toulouse, France, June 30-July 5, 1986, and will be included in part I1 of the Conference proceedings (Edited by B. Hultqvist).'pectrum is taken during Physica Scripta 37