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Appendix B:Prime Campaign Missions and Payloads

Mission Index

The GEOTAIL Mission and Payload

GEOTAIL instruments will study the flow of energy and its transformation in the magnetotail, and also clarify the mechanisms of input, transport, storage, release, and conversion of mass, momentum, and energy in the magnetotail. GEOTAIL will use the gravity of the Moon to assist it to keep orbiting on the night side of the Earth. Initially, GEOTAIL's orbit will range from 220 Re (1,401,620 km) from the Earth at its farthest point to 8 Re (50, 960 km) at its closest point. In November 1994, the spacecraft will be repositioned to an orbit of 8 x 30 Re.

Key GEOTAIL Mission Statistics:

Launch vehicle:       Delta II     S/C Power--EOL         (3 yr): 340 Watts
S/C dry weight:       649 kg       S/C Telemetry          rate (RT): 16 kbps
Fuel weight:          360 kg       S/C Telemetry rate     (PB): 131/65 kbps
Instrument weight:    105 kg       S/C Command            Rate: 100 bps
Total weight:         1009 kg      S/C Spin Rate:         20 rpm

GEOTAIL Instruments

1) Electric Field Detector (EFD)--

Dr. K. Tsuruda, Principal Investigator (PI)

The DC and quasi-DC electric field are believed to play important roles in the dynamics of the solar wind-magnetosphere system. The plasma motion in the tail lobe across the magnetic field is key information in the study of tail formation and the stability of the plasma sheet. Cross-field plasma motion in the tail lobe had not been measured with sufficient reliability in the past survey due to the lack of proper measuring techniques. The EFD will measure the cross-field electric field in the tail lobe by a newly developed technique--an electron boomerang technique--and provide information on plasma motion across the tail lobe.

The EFD consists of three different instruments: EFD-b, an electron boomerang device; EFD-p, double probes; and an ion emitter to neutralize charging of the spacecraft by the electron beam ejection.

EFD-b measures the electric drift motion of the electron beams emitted from the spacecraft perpendicular to the magnetic field. If the electric field is absent, the electron beam emitted returns to the spacecraft after one gyro period. However, if the electric field is present, the beam returns to the spacecraft only when the beam is injected in a proper direction with respect to the electric field. There are two such directions: one is nearly parallel to the electric drift velocity and the other is nearly anti-parallel to it. The time necessary for one beam to return to the spacecraft is a little longer than the gyro period and the time for the other beam is shorter by the same small amount than the gyro period. The small difference in the time is proportional to the magnitude of the electric field. From the gyro period, the magnetic field intensity can be obtained; and from the small correction, the magnitude of the electric field can be derived. The direction of the electric field can be derived from the direction of the beam.

EFD-p is an instrument based on the conventional double-probe technique which measures the potential difference between the two electrodes extended from the spacecraft. EFD-p uses two types of electrodes. One is a pair of sphere probes extended 50 meters from the spacecraft by a flexible cable and the other is a pair of wire antennas extended 50 meters from the spacecraft in the orthogonal direction from the sphere probes.

2) Magnetic Field Experiment (MGF)-

Dr. S. Kokubun, PI

The MGF will measure magnetic field variations in the frequency range below 50 Hz, using fluxgate magnetometers and a search coil magnetometer. The science objectives of MGF are to examine the following questions:

The MGF consists of dual three-component flux gate magnetometers and a three-component search coil magnetometer for measurement of magnetic variations in the frequency below 50 Hz. Triad flux gate sensors (outboard and inboard sensors), which utilize a ring core geometry, are installed at the end and the middle of a 6-m deployable mast. This configuration allows the in-flight, real-time estimation of the spacecraft field, and also provides redundant measurements. The inboard magnetometer (a triad sensor and analog electronics) supplied by GSFC is similar to those used in the successful AMPTE mission and other NASA missions. The A/D conversion, data processing and automatic range change for the two magnetometers are controlled by a microprocessor unit (MPU) in the system.

Three search coils are mounted approximately half way out on another 6-m boom, together with search coils for VLF wave measurements by the PWI. Signals detected by the search coil sensors of the MGF are also used in the PWI. Data from flux gate magnetometers are sent in the same format for both real-time and recorded modes, while search coil data are obtained only in real-time mode.

Sampling rates for A/D conversion controlled by MPU will be 4 or 8 times of 16 Hz for both magnetometers. Sampled signals are averaged and sent to the Data Processing Unit of the spacecraft for telemetry. The exchange mode to change telemetry rates between the outboard and inboard magnetometers will be prepared. Analog signals from either the outboard magnetometer or the inboard one are fed to the EPIC, EFD, and PWI instruments and to the A/D converter for the housekeeping monitor in the DPU system.

3) High Energy Particle Experiment (HEP)-- Dr. T. Doke, PI

The instruments in the HEP experiment include four spectrometers: a Low Energy Particle Detector (LD), a Burst Detector (BD), a Medium Energy Isotope Telescope (MI), and a High Energy Isotope Telescope (HI). The energy ranges of these detectors are listed as follows:

LD   Electron       20 keV-300 keV
     Ion            2 keV/nucl-1.5 MeV

BD  ElectroN        0.12-2.5 MeV
    Proton, Helium  0.7-3.5 MeV/n
    Proton          3.5-35 MeV/n
    Helium          3.5-35 MeV/n

               nuclear charge      nuclear mass
MI-1    He     2.4-20 MeV/n        2.4-15 MeV/n
        C      4.5-38              4.5-38
        Ne     5.5-50              5.5-50
        Mg     6.0-55
        Si     6.2-60
        Fe     7.5-80

MI-2    C      6.5-40 MeV/n        6.5-40 MeV/n
        Ne     8.0-52              5.5-52
        Mg     9.0-60              9.0-60
        Ca     12.0-80             14.0-74
        Fe     13.0-80             16.0-65
        z      > 45                14.0-120

HI      He     10-55               10-40
        C      18-110              18-110
        Ne     24-130              24-130
        Mg     26-160	           26-160
        Si     28-180	           28-180
        Ca     34-210	           34-210
        Fe/Ni  38-210	           21-210

The HEP-LD, with full coverage of the unit sphere in velocity space, large energy range, and high time resolution, can scrutinize unexplained phenomena such as:

The major objective of the BD sensor is to study particle acceleration events occurring in the magnetotail. The relatively large geometrical factor (0.76 cm str) of the detectors will allow studies of the 3-D anisotropy of particles of greater than 100 keV with time resolution of less than 10 sec. Monitoring of time variations in the energy spectrum of incident particles with high time resolution is a key for clarification of the nature of their acceleration mechanisms.

The highly sophisticated instruments, HEP-MI and HEP-HI spectrometers, provide detailed measurements of the energy spectrum and isotope composition of solar energetic particle (SEP) events and the other energetic particles in the heliosphere, such as anomalous cosmic rays and galactic cosmic rays.

The HEP-LD spectrometer is designed for the fast analysis of energetic electrons and ions with a complete coverage of the unit sphere in phase space. State-of-the-art techniques are employed to accomplish particle discrimination and three-dimensional analysis in phase space. The instrument consists of a single unit which contains the sensor units of three identical Imaging Ion Mass Sensor Units (IIMSU) and a Digital Preprocessing Unit (HEP-LD/DPU).

Identification of electron, proton, and helium by the BD instrument is based on the silicon [[Delta]]E - E telescope system. The energy loss ([[Delta]]E) is pro-portional to Mz2/E, where M is mass and z is charge.

The HEP-MI instrument measures the elemental and isotopic compositions of solar energetic particles and energetic particles in the heliosphere with 2 < z < 28 in the comparatively low- and medium-energy region (2.4 to 80 MeV/n) and, furthermore, measures the elemental composition of the SEP heavier- than-iron group. The HEP-HI also measures the elemental and isotopic compositions of SEP and galactic cosmic rays with 2 < z < 28 in the high-energy region (10 to 210 MeV/n). The HEP-MI and -HI instruments are all silicon semiconductor detector telescopes utilizing the well-known algorithm of delta-E x E.

4) Low Energy Particle Experiment (LEP)-- Dr. T. Mukai, PI

The LEP experiment will make comprehensive observations of plasma and energetic electrons and ions with good temporal and parameter resolutions in the Earth's magnetosphere (mainly in the magnetotail) and in the interplanetary medium. The major scientific objectives are to study the following subjects:

The LEP instrument consists of three sets of sensors (LEP-EA, LEP-SW and LEP-MS) and a common electronics (LEP-E). With this configuration of the instrument, the LEP is capable of providing measurements of the following:

The LEP-EA uses two quadrispherical electrostatic analyzers, the inner one to measure electrons over the energy range from 6 eV to 36 keV and the outer one to measure positive ions from 8 eV/Q to 42 keV/Q. The field of view for each quadrispherical analyzer covers 10deg. x 145deg., where the longer dimension is parallel to the satellite spin axis. The detectors are placed at the positions corresponding to the incident elevation angles of 0deg., +22.5deg., +45.0deg. and +67.5deg., respectively. One spin period is divided into 16 azimuthal sectors, and in each sector the electron and ion energies are scanned over the whole or selected range which consists of 32 steps. Thus the LEP-EA, separately and simultaneously, can measure the three-dimensional energy/charge (and velocity with assumption on ion species) distributions of electrons and positive ions in one spin period.

The protons and alpha particles in the solar wind with the bulk velocity of 150 to 800 km/s fall into the range of the LEP-SW measurement, while heavier ions can be measured by the LEP-EA. The measurement principle and the method of the LEP-SW are quite similar to that of the LEP-EA ion analyzer.

The LEP-MS is an energetic ion mass spectrometer, which determines the ion composition with measurement of three-dimensional velocity distributions of the ion species over the energy range of 0 to 25 keV/Q (in 32 steps). It is composed of an inlet collimator, a spherical electrostatic analyzer, an orange-type magnetic analyzer and microchannel plate (MCP) detectors. The ion composition data, which consist of (4 energy steps) x (16 azimuthal sectors) x (5 elevation angular bins), are produced in one spin period, and the data for the next four energy steps are obtained in the next spin period. Therefore the complete scanning of 32 energy steps takes 8 spin periods. The maximum and minimum measured energies can be flexibly specified by the BC command.

The LEP-E consists of low-voltage electronic circuits, the functions of which are to control the energy, angular, and mass sampling, to gather data from the sensors (LEP-EA, LEP-SW and LEP-MS), to perform the moment calculations from the data of the LEP-EA and LEP-SW sensors, and to interface the DHU for decoding the LEP commands, formatting the LEP data and monitoring the housekeeping data. It also outputs the trigger (burst) signal for the PWI waveform capture when the result of the moment calculations exceeds a certain level specified by the BC command.

5) Plasma Wave Instrument (PWI)--

Dr. H. Matsumoto, PI

The plasma wave instrument will take the role of measuring plasma waves from 5 Hz up to 800 kHz. The PWI is composed of three different sets of receivers. They are:

The first two receivers are dedicated to the measurement of wave spectra while the third is used to measure the five simultaneous wave forms from five different antennas. The antennas used for the PWI are one of the two tri-axial magnetic search coils and one of the two electric antennas. One of the electric antennas is a pair of wire dipole antennas with a length of 100 m tip-to-tip, and the other is a pair of spherical antennas mounted on the top of a boom with a length of 100 m tip-to-tip.

The SFA provides amplitude and spectral information on plasma waves over the frequency range of 24-800 kHz for electric field and 24 Hz-12.5 kHz for magnetic field. The SFA has five frequency bands:

Band #l	25-200 Hz	(B and E)
Band #2	200-1600 Hz	(B and E)
Band #3	1.6-12.5 kHz	(B and E)
Band #4	12.5-100 kHz	(E only)
Band #5	100-800 kHz	(E only)

Each frequency band has 128 frequency steps. The lowest-frequency band (#1) is swept in 128 seconds, and the four other bands are swept in 8 seconds simultaneously. The SFA has a dynamic range of about 70 dB.

The multi-channel Analyzer (MCA) consists of a 20 channel analyzer covering the frequency range from 5.62 Hz to 311 kHz for electric field components, and a 14-channel analyzer covering the frequency range from 5.62 Hz to 10 kHz for the magnetic field components. The band widths are of 15% of the center frequency up to 10 kHz, and 7.5% above 10 kHz. All channels are sampled simultaneously.

The WFC is used for a detailed analysis of the mode of the measured waves; for example, for the k-vector determination and the calculation of the Poynting flux. The WFC has five amplifiers connected to five antennas respectively. The simultaneous wave forms of Bx, By, Bz, Ex, and Ey are stored in the 4 Mbit memory at high speed. The stored data are replayed slowly with a period of 260 seconds and sent back to the ground by the PCM telemetry. The data taken by the WFC are five simultaneously sampled wave forms in the frequency range of 10 Hz to 4 kHz for a period of 8.3 seconds. The start timing of the sampling of the wave form in the WFC is controlled by several different types of triggering signals.

6) The Comprehensive Plasma Instrumentation (CPI), Dr. L. A. Frank,PI

The CPI will obtain three-dimensional plasma measurements in Earth's magnetotail and its environs. It is based upon the principal elements of design of the ISEE and Galileo plasma instruments and incorporates several substantial improvements in design. The instrumentation comprises:

The hot plasma analyzer measures the directional, differential energy spectra of positive ion and electron intensities over the energy/charge range 1 eV/Q to 50 keV/Q, separately and simultaneously, with a full-width, half-maximum energy resolution [[Delta]](E/Q)/(E/Q) = 0.10. All but 1% of the entire 4[[pi]]-steradian solid angle for charged particle velocity vectors at the satellite position is within the analyzer's field-of-view and is covered with good angular resolution.

The solar wind ion analyzer has an energy/charge range of 150 eV/Q to 7 keV/Q and full-width, half-maximum energy resolution [[Delta]](E/Q)/(E/Q) = 0.03. The corresponding angular coverage and resolution are sufficient to provide fast, definite observations of three-dimensional solar wind ion velocity distributions.

The ion composition analyzer comprises a quadrispherical electrostatic analyzer with five miniature imaging mass spectrometers at its exit aperture. Measurements of mass (M/Q) composition over a range extending from H+ to Fe+ are gained simultaneously in 330 mass channels with good sensitivity and temporal resolution <= 3 seconds. Angular coverage is 70% of 4[[pi]] steradians with good angular resolution. The energy/charge range of the ion composition analyzer is 1 eV/Q to 50 keV/Q.

The above three analyzers can be operated independently and/or interactively via the instrument microprocessors to achieve flexibility and excellent temporal resolution in the measurements of plasma parameters. Among the scientific objectives of the CPI are:

7) Energetic Particles and Ion Composition (EPIC) Experiment-Dr. D. Williams, PI The science objectives of the Energetic Particles and Ion Composition (EPIC) Experiment include the following:

The EPIC instrument contains two ion composition spectrometers: the Supra-Thermal Ion Composition Spectrometer (STICS) and the Ion Composition Subsystem (ICS) sensors. These measure charge state, mass, and energy of ions from 50 keV to 3 MeV and from 10 to 230 keV/Q. This will be used to determine the relative importance of ion sources and mechanisms for acceleration, transport, and loss of particles. The formation and dynamics of boundary layers and their influence on magnetospheric behavior will be studied.

The sensor signals are sent to analog electronics to be further amplified, processed for timing and position information, and digitized. Digitized data from both of the analog sensor electronics then go to the Data Processing Unit, where the data are analyzed and stored. In addition, the DPU also handles all command decoding and processing, telemetry formatting and interface, power switching, and instrument control.

The WIND Mission and Payload

The WIND spacecraft will be launched into a figure-eight orbit around the Earth and the Moon on the Sun side of the Earth. The apogee will be 250 Re and perigee, 5 Re. The satellite will spin at 20 revolutions per minute. In the early-phase double-lunar-swingby orbit, the line of apsides is held close to the Sun-Earth line throughout the year by means of lunar swingby maneuvers. From this orbit, WIND will measure properties of the solar wind plasma before it reaches the Earth and will observe the foreshock, where turbulence is produced by particles reflected from the bow shock. After the lunar swingby orbit phase, WIND will be inserted into a small L1 halo orbit, near 250 Re to continuously provide optimum measurements of the solar wind.

Key WIND Mission Statistics

Launch date: December 12, 1993
Launch vehicle: Delta II 7925
Orbit: Initial: Dayside Double-Lunar-Swingby;
Perigee: 5-10 Re;
Apogee: 80-250 Re;
Inclination: Lunar orbit plane +/- 5deg.
Final: Halo orbit at Sun/Earth L1 point; Earth distance:
235-265 Re;Halo semi-major axis: 25-104 Re;
Ecliptic declination fromEarth: +/-5deg.
Mission duration: 3 years nominal
S/C dry weight: 826 Kg (approx.)
Fuel weight: 354 Kg (approx.)
Instrument weight: 160 Kg (approx.)
Total weight: 1330 Kg (approx.)
S/C power: Solar cell; 417 W BOL, 309 W EOL (depending on Sun angle)
Spin rate: 20 rpm (de-spun platform)
Dimensions : Height: 1.85 m;
diameter: 2.44 m
Data storage: 2 tape recorders, 1 x 109 bit/unit
Communications: S-band
Scientific data rates: Tracking mode (real-time): 5.56 Kbps (11.1 Kbps option For operations inside 60 Re)
Playback mode: 512 Kbps(128 Kbps option for operations inside 60 Re)
Nominal contact time: 2.5 hr/day

WIND Instruments

1) Radio and Plasma Wave (WAVES)--

Mass: 32.0 Kg; Data Rate: 1.0 Kbps;

Dr. J. Bougeret, PI

The WAVES experiment will provide comprehensive measurements of the radio and plasma wave phenomena which occur in the solar wind upstream of the Earth's magnetosphere and other magnetospheric regions over a very wide frequency range (DC to 14 MHz). Analyses of these measurements, in coordination with the other onboard plasma, energetic particle, and field measurements, as well as the other campaign observations, will be used to study important kinetic processes in the solar wind, understand the interactions between the interplanetary plasma and radio waves emitted from the Sun and the Earth, and identify the mass, momentum, and energy flow throughout geospace.

The sensor system of the WAVES instrument consists of three electric antenna systems (two are coplanar, orthogonal wire antennas (Ex and Ey) in the spin-plan, the other a rigid spin-axis dipole (Ez), and a triaxial magnetic search coil. The longer dipole (Ex) and shorter dipole (Ey) have a length of 90 and 15 m tip-to-tip, respectively, while the spin-axis dipole (Ez) has 11 m tip-to-tip long. The magnetic search coil and its preamplifiers are similar to those developed for the POLAR spacecraft.

WAVES employs five main receiver systems: a low-frequency (DC to 10 kHz) FFT receiver, a broadband (4 kHz to 256 kHz) multi-channel analyzer designed principally to study the electron thermal noise, two dual radio receivers covering the band 20 kHz to 16 mHz, and a time-domain waveform sampler (sampling to 120,000 samples/s). The principal characteristics of the receiver systems are summarized in the following table.

Low Frequency Fast Fourier Transform Receiver (FFT)
     Input              Ex, Ey, Ez, Bx, By, and Bz
     Frequency Range    DC to 10 kHz
     No. Channels       2 channels for DC to 10 kHz,
                        4 channels for DC to 2.5 kHz,
                        4 channels for DC to 170 Hz
     Sensitivity        1 microvolt
     Dynamic Range      120 dB

Thermal Noise Receiver (TNR)
     Input              Ex, Ey, and Ez
     Frequency Range    4 kHz to 256 kHz
     No. Channels       320 or 160 (in 5 bands)
     Bandwidth          400 Hz to 6.4 kHz
     Sensitivity        5 nV/root Hz

Radio Receiver Band 1 (RAD1)
     Input              Ex + Ez, and Ez
     Frequency Range    20 kHz to 1 MHz
     No. Channels       256
     Bandwidth          3 kHz
     Sensitivity        5 nV/root Hz

Radio Receiver Band 2 (RAD2)
     Input              Ey + Ez, and Ez
     Frequency Range    1 MHz to 14 MHz
     No. Channels       256
     Bandwidth          35 kHz
     Sensitivity        5 nV/root Hz

Time Domain Sampler (TDS)
     Input              4 of Ex, Ey, Ez, Bx, By, and Bz
     Sample Rate        up to 120 kHz per channel
     Memory             256 Kbytes
     No. Channel        2 at 120,000 samples/s, 
                        4 at 7,500 samples/s
     Sensitivity        1 microvolt

2) Solar Wind Experiment (SWE)--Mass: 12.0 Kg; Data Rate: 600 bps; K. Ogilvie, PI

The SWE for the WIND spacecraft is a comprehensive, integrated set of sensors which will attack most outstanding problems in the magnetosheath, the foreshock, and the interplanetary medium. It will provide high-sensitivity measurements of low-mach-number plasma distribution functions to study the foreshock and reflected ions from Earth's bow shock; fast time resolution and accurate measurements of high-mach-number plasma distribution functions and solar wind flux, density, temperature, momentum flux to study the solar wind and its fluctuations and the transfer of energy and momentum from the Sun to the Earth; and high-angular-resolution measurements of electron beams to study electrons moving along the interplanetary field direction towards and away from the Sun.

The SWE instrument consists of two Vector Electron and Ion Spectrometer (VEIS) subsystems, two Faraday cup subsystems and a single Strahl sensor. VEIS will make 3-D velocity distribution measurements of ions and electrons from 10 eV to 22 keV for plasma having mach numbers less than 1 by using 6 cylindrical electrostatic analyzers, which are in sets of 3 and each pair directed along orthogonal directions. The Faraday cups will make 3-D velocity distribution measurements of ions from 100 eV to 8 keV in the solar wind. The Strahl sensor, a single wide-angle toroidal electrostatic analyzer with a multi-anode channel plate sensor, will make electron velocity distribution and pitch angle measurements from 5 eV to 5 keV as the +/- 30deg. x +/- 2deg. solid angle passes through the magnetic field direction. The basic parameters of the SWE sensors are listed below:

VEIS	
      Energy Range            10 eV-22 keV
      Energy Resolution       [[Delta]]E/E ~ 0.06
      Field of View           11deg. x 8deg.
      Angular Resolution      6deg.
      Time Resolution         > 0.5 second
      Geometric Factor        1.8 x 10-4 cm2 sr
      Weight/Power            3.2 Kg/2.2 watts

Faraday cup
      Energy Range            00 eV-8 keV
      Energy Resolution       [[Delta]]E/E >= few percent
      Field of View           +/- 60deg. x +/- 60deg.
      Angular Resolution      < 1deg.
      Time Resolution         ~ 1 second
      Weight/Power            2.6 Kg/3.0 watts

Strahl sensor
      Energy Range            5 eV-5 keV
      Energy Resolution       [[Delta]]E/E ~ 0.05
      Field of View           +/- 30deg. x +/- 2deg.
      Angular Resolution      4deg.
      Time Resolution         ~ 3 sec
      Weight/Power            1.7 Kg/0.8 watts

3) Magnetic Field Investigation (MFI)-- Mass: 2.65 Kg; Data Rate: 512 bps;

Dr. R. Lepping, PI

The MFI is a precise (0.025%), accurate (< 0.08 nT) and ultra-sensitive (0.008 nT/step) magnetometer designed to investigate the large-scale structure and fluctuation characteristics of the interplanetary magnetic field (IMF), which influence the transport of energy and the acceleration of particles in the solar wind and dynamic processes in the Earth's magnetosphere. The fundamental observations of solar wind magnetic fields are especially important to the study of the solar wind and the magnetosphere coupling process, and also to the interpretation of other observational data from WIND.

The basic configuration of MFI consists of dual, wide range (+/- 0.004 nT to +/- 65536 nT) triaxial fluxgate magnetometers and a microprocessor- controlled data processing and control unit (DPU). Total RMS noise level of the MFI fluxgate sensors over the 0-10 Hz band does not exceed 0.006 nT, which is several orders of magnitude below the lowest recorded levels of IMF fluctuations at 1 AU and is more than adequate to properly detect and identify all magnetic field phenomena of interest to MFI. The MFI will provide near-real-time data at three measurement rates: nominally one vector per 92 seconds for key parameter data, 10.8 vectors/second for rapid data for standard analysis, and 44 vectors/second for snapshot memory data and Fast Fourier Transform (FFT) data.

MFI Characteristics:

     Instrument type                 Dual, triaxial fluxgate magnetometers (boom mounted)
     Dynamic ranges(8)	             +/- 4 nT; +/- 16 nT; 
                                     +/- 64 nT; +/- 256 nT; 
                                     +/- 10245 nT; 
                                          +/- 4096 nT; +/- 16,384 nT;
                                     +/- 65,536 nT
     Digital resolution              +/- 0.004 nT; +/- 0.016 nT; 
                                     (12-bit A/D)	+/- 0.0625 nT; +/- 0.25 nT; 
                                     +/- 1.0 nT; +/- 4.0 nT; 
                                     +/- 16.0 nT
     Sensor noise level              < 0.006 nT RMS, 0-10 Hz
     Sampling rate	                  44 vector samples/second
     Signal processing               Fast Fourier Transform(FFT) Processor, 32
                                     logarithmically spaced channels, 0 to 22 Hz.
                                     Full spectral matricesgenerated every 46 s (lowest) or 
                                     23 s (highest) for four time series 	
                                    (Bx, By, Bz, and |B|).
     FFT windows/filter              Full de-spin of spin plane components, 10% cosine
                                     taper, Hahn, first difference filter
     FFT dynamic range               72 dB, Log-compressed, 12 bit to 7 bit + sign
     Sensitivity threshold	          ~ 0.5 x 10-3 nT/[[radical]]Hz in Range 0
     snapshot memory capacity        256 Kbits
     Snapshot triggermodes (3)       Magnitude, Direction,Spectral (RMS)
     Telemetry modes 3,              selectable by ground command
     Mass Sensors (2):               450 g; Electronics (redundant): 2100 g
     Power consumption               2.4 watts

4) Energetic Particle Acceleration, Composition, and Transport (EPACT)--Mass: 25.9 Kg;

Data Rate: 500 bps; Dr. T. von Rosenvinge, PI

The high-sensitivity EPACT instrument will study the acceleration, elemental composition and transport of a wide variety of energetic particle pop-ulations in individual impulsive flare events, interplanetary shock events and, potentially, it will make the first observations of ultra-heavy nuclei in solar flares. It will measure the elemental and isotopic abundances for the minor ions making up the solar wind with energies in excess of 20 keV, and measure the isotopic composition of energetic particles in the anomalous component and in the galactic cosmic rays. EPACT will also provide information on shocks in the interplanetary medium, which accelerate particles from solar wind energies to several hundred keV.

The EPACT experiment consists of three Low Energy Matrix Telescopes (LEMT), two Alpha-Proton-Electron Telescopes (APE), an Isotope Telescope (IT), and a Supra-Thermal Energetic Particle Telescope (STEP). All but STEP use the dE/dx by E method of particle identification. STEP measures time-of-flight and energy, from which particle mass can also be obtained. The EPACT telescope characteristics are listed below.

                            LEMT          APE-A	
Charge range                1 ~ 90           -1 ~ +26
Energy range: 	
     Electrons (MeV)        --               0.2 ~ 2	
     Helium (MeV/n)         1.1 ~ 11         4.3 ~ 2519
     Iron (MeV/n)           1.7 ~ 43         14 ~ 100	
Geometric factor (cm2 sr)   3 x 17             1.2
Isotope resolution          He3/He4             He3/He4
                            APE-B        IT
Charge range                 -1 ~ +26       2 ~ 26	
Energy range: 
   Electrons (MeV)           1 ~ 10         --	
   Helium (MeV/n)            ~ 500          3.4 ~ 85	
   Iron (MeV/n)              73 ~ 300       10 ~ 360	
Geometric factor (cm2 sr)    1.6             8	
Isotope resolution           He3/He4         Fe, [[Delta]]M=0.3

                            STEP
Charge range                 2 ~ 26
Energy range:		
   Electrons (MeV)           --
   Helium (MeV/n)            < 0.1 ~ 10
   Iron (MeV/n)              < 0.1 ~ 1
Geometric factor (cm2 sr)    2 x 0.4
Isotope resolution           He3/He4

5) Solar Wind and Suprathermal Ion Composition Experiment (SMS)--Mass: 27.0 Kg;

Data Rate: 870 bps; Dr. G. Gloeckler, PI

The SMS on WIND will measure uniquely the elemental, isotopic, and ionic-charge composition of solar wind ions over a range of 0.3 to 2 keV/e, the differential energy spectra (and thus the densities, bulk speeds and kinetic temperatures) of all major solar wind ions, form H to Fe at solar wind speeds from 130 km/s (Fe+10) to 2400 km/s (protons), and the composition charge state as well as the 3-dimensional distribution functions of suprathermal ions of energies between 0.1 to 230 keV/e.

The major scientific objectives of the SMS are to provide the instantaneous characteristics of matter entering the Earth's magnetosphere by measuring the mass, charge state, and energy distributions of solar wind suprathermal ions; to determine solar abundances by measuring the elemental and isotopic composition of the solar wind; to study solar wind acceleration, especially of minor ions using solar wind composition and charge state measurements; to study physical processes in the solar atmosphere by measuring the abundances of all elements between He and Ni, thus spanning the full range of first ionization potentials; to characterize the physical properties of the acceleration regions in the lower corona by measuring the solar wind charge state distributions of several ion species (e.g., C, O, Ne, Mg, Si and Fe); to study plasma processes affecting the solar wind kinetic properties and producing suprathermal ions by measuring energy spectra and distribution functions of major ion species over the full energy range of SWICS and STICS; to study interplanetary acceleration mechanisms producing shock-accelerated energetic storm particle events and upstream ions using measurements of the three-dimensional distribution functions of H, He, C, O, Si, and Fe; and to study interstellar ion pick-up processes by measuring the three-dimensional distribution functions of He+.

The SMS experiment consists of three major instruments: the Solar Wind Ion Composition Study (SWICS), the "Mass" Sensor (MASS), and the Suprathermal Ion Composition Study (STICS). By using a combination of electrostatic deflection, moderate post-acceleration, a time-of-flight and energy measurement, SWICS will accurately measure the mass and charge composition of the solar wind. As a straightforward extension of SWICS but without using post-acceleration, STICS has a large geometric factor and nearly 4[[pi]] viewing capabilities required for studies of suprathermal tails of distribution functions, and of diffuse ions, shock-accelerated ions and pick-up ions. MASS will be the first instrument flown with capabilities for high-mass resolution (M/[[Delta]]M > 100) measurements of the solar wind ion composition. MASS uses energy/charge analysis followed by a time-of-flight measurement in a retarding, quadratically changing electric potential. The major capabilities of SMS are listed in the following table.

SMS Instrument Capabilities

SWICSMASS
Ion speciesH-FeHe-Ni
Mass/charge range (amu/e)1-30-
Energy range (keV/e)0.5-300.5-11.6* Mean speed range (km/s)
H+310-2400-
O+6190-1470200-900
Fe+10130-1010200-500 Resolution (FWHM)
Energy,[[Delta]](E/Q)/(E/Q)0.060.05
Mass/charge,[[Delta]](M/Q)/(M/Q)0.04-
Mass, [[Delta]]M/M0.20.01
Geometrical factor 9 x 10-3 cm20.28 cm2
Dynamic range10101010
Minimum flux10-2 (cm2 s)-110-2(cm2 s)-1
STICS
Ion species H-Fe
Mass/charge range (amu/e)1-60
Energy range (keV/e)8-226
Mean speed range (km/s)
H+-
O+6-
Fe+10 -
Resolution (FWHM)
Energy, [[Delta]](E/Q)/(E/Q)0.05
Mass/charge,0.15[[Delta]](M/Q)/(M/Q)
Mass, [[Delta]]M/M0.12
Geometrical factor0.05 cm2 sr
Dynamic range5 x 1010
Minimum flux10-6(cm2 s sr keV/e)-1
* Species dependent

6) Three-Dimensional Plasma Analyzer (PLASMA)-- Mass: 18.2 Kg; Data Rate: 1.035 Kbps;

Dr. R. Lin, PI

With high sensitivity, wide dynamic range and wide angular coverage, good energy and angular resolution, and high time resolution, the 3-D PLASMA will provide measurements of the full three-dimensional distribution of suprathermal and energetic electrons and ions. It covers the energy range between solar wind and cosmic ray energies, a few eV to several hundred keV, bridging the energy gap between the SWE and EPACT instruments. The goals of the experiment are to explore the interplanetary particle population in the suprathermal energy range; to identify the particle and plasma input to and output from the Earth's magnetosphere; to study the particle acceleration at the Sun, in the interplanetary medium, upstream of the Earth's bow shock and in the foreshock region; and to study basic plasma processes such as wave-particle interactions.

The 3-D PLASMA instrument consists of three detector systems: The semiconductor detector telescopes (SST), the electron electrostatic analyzers (EESA), and the ion electrostatic analyzers (PESA). The SST is to measure electron and ion fluxes above ~ 20 keV. EESA-L and -H and PESA-L and -H are pairs of electrostatic analyzers with widely different geometric factors to cover the wide range of particle fluxes from ~ 3 eV to 30 keV and provide significant measurements even at the lowest flux levels likely to be encountered. In addition there is a fast particle correlator (FPC) for the measurement of the perturbation to the electron distribution function on fast time scales in wave-particle interactions upstream of the Earth's bow shock, and in the interplanetary medium. EESA-H is also used in the FPC and has electrostatic deflectors to follow the magnetic field. The major instrument characteristics and measurement parameters are summarized as follows.

3-D PLASMA Instrument Characteristics:

                                    Mass (kg)     Power (W)     Size (cm)          Bit rate     
EESA-H and EESA-L Boom Unit         5.2           3.2           31x35x25*
PESA-H, PESA-L and SST Boom Unit    5.6           4.0           33x27x25*
Main DPU/SST Analog Box             7.4           8.4           20x20x26
Total                               18.2          15.6                             1035bps**

* Approximate outside dimensions

** Bit rate doubles inside 60 Re

3-D PLASMA Measurement Parameters:

EESA-H/FPCEESA-LPESA-HPESA-L
Particle specieseepp
Energy range (E)0.1-30keV3 eV-30 keV3 eV-30 keV3 eV-30 keV
Energy resolution ([[Delta]]E/E)0.200.200.200.20
Geometric factor (cm2 sr)0.1 E1.3 x 10-2 E 1.5 x 10-2 E 1.6 x 10-4 E
Field-of-View360deg.x 90deg.*180deg.x 14deg.360deg.x 14deg.180deg.x 14deg.
Angular resolution5.6deg.x 5.6deg.**5.6deg.x 5.6deg.**5.6deg.x 5.6deg.**5.6deg.x 5.6deg.**
Dynamic range (cm2 sr s)-1~ 1-102 ~102-109~ 1-109~104-1011

*14deg. FOV electrostatically deflected up to +/- 45deg. to follow magnetic field

** High angular resolution available only +/- 22.5deg. from ecliptic plane

Semiconductor Detector Telescope (SST):

SST-Foil (F)SST-Magnetic (O)SST-Telescope (FT & OT)
Particle speciese pep
Energy range (E)25-400 keV20 keV-6 MeV0.4-1 MeV6-11 MeV
Energy resolution ([[Delta]]E/E) 0.30.30.30.3
Geometric factor (cm2 sr) 1.7*1.7*0.36**0.36**
Field-of-View180deg.x 20deg.*180deg.x 20deg.*72deg.x 20deg.**72deg.x 20deg.**
Angular resolution22.5deg.x 36deg.22.5deg.x 36deg.22.5deg.x 36deg.22.5deg.x 36deg.
Dynamic range (cm2 sr s)-1 ~ 0.1-106~ 0.1-106 ~ 10-2-106 ~10-2-106
* Five detectors cover the 180deg. FOV, with geometric factor 0.33 cm2 sr each
** Two detectors cover the 72deg. FOV, with geometric factor 0.33cm2 sr each

7) Transient Gamma Ray Spectrometer (TGRS)-- Mass: 18.23 Kg; Data Rate: 376 bps; Dr. B. Teegarden, PI

TGRS will observe transient cosmic gamma-ray burst (GRB) events and will make the first high-resolution spectroscopic survey of cosmic gamma-ray transients with fine time resolution and wide field-of-view over the energy range 15 keV to 10 MeV. Besides burst measurements, it will also study transient phenomena of solar flares since they are morphologically similar to GRB's. The high-resolution spectroscopy on solar flares will study solar flare activities, and help in understanding the coupling between the active corona and photosphere. Moreover, it will be used to study particle acceleration and the impulsive release of energy in an astrophysical plasma. TGRS will also search for possible diffuse background lines and monitor the 511 keV positron annihilation radiation from the galactic center.

The Principal TGRS Experimental Characteristics:

       Detector              High purity n-type germanium crystal in the reverse electrodeconfiguration 
       Dimensions            6.7 cm (diameter) x 6.1 cm (length)
       Energy range          15 keV to 8.2 MeV
       Energy resolution     2.0 keV @ 1 MeV (E/[[Delta]]E = 500)
       Field-of-View         170deg. FWFM geometric
       Sensitivity           better than 10-7 ergs cm2 for 60-second burstduration
       Subsystems            Detector, Cooler, Analog Processing Unit (APU),
                             and Digital Processing Unit (DPU)
       Occulter              Modulation factor in the ecliptic plane = 25%
                             Attenuation ~ 10 @ 511 keV
       Cryogenics            Two stage passive cooler of radiating area ~ 1600 cm2
                             inner state temperature 85 K; outer stage temperature 164 K 
       Detector/cooler       assembly weight 6.1 kg;  46 cm diameter, x 17 cm thick
       Temporal resolution   62 us intrinsic; +/- 1.5 ms after ground processing
       Memory size           2.75 million bits
       Total power           6.95 watts quiescent; 26 watts heater power (low duty cycle)
       Data File             Type                                          Memory allocation (16 bit words)
                             event-by-event above ADC ch 200               110 K (plus 70 K for burst mode)
                             200 ch histograms                             45 K
                             1024 ch spectra                               2 K
                             8192 ch spectra                               16 K
                             Sectored windows 64 ch's, 4 energy ranges     50 K
                             11 rates                                      12 K

8) Gamma Ray Spectrometer (Konus)--Mass: 22 Kg; Data Rate: 55 bps, Drs. E. Mazets/T. Cline, PI's

As a result of the U.S./Russian Space Agreement of 1988, the Russian instrument Konus will fly on the WIND spacecraft to continuously monitor cosmic gamma-ray bursts and solar flares in the energy range 10 keV-10 MeV. Combined with TGRS data, the results of Konus will be used to study burst time profiles, burst spectral composition and variability in both the continuum and line emissions, to measure the emission and absorption line features in bursts and identify the burst sources, and study the timing and spectra of impulsive solar flares.

There are two sensors, S1 and S2, four amplitude analyzers for pulse height analysis (PHA 1, 2, 3, 4), four time history analyzers (THA 1, 2, 3, 4), two high-resolution time history analyzers (HRTHA 1, 2) and a background measurement system (BM) in the Konus instrument. The two sensors, copies of ones successfully flown on several Soviet missions, are identical and interchangeable NaI scintillation crystal detectors of 200 cm2 area and shielded by Pb-Sn. They ensure practically isotropic angular sensitivity.

Their characteristics are:

Energy range              SG1:              10-50 keV 
                          SG2:              50-200 keV
                          SG3:              200-770 keV       
                          SZ:               > 10 MeV       
                          A1 (ES1):         10-770 keV       
                          A2 (ES2):         0.2-10 MeV       
Energy resolution         E/[[Delta]]E = 15 at 200 keV       
Field of View             2[[pi]] steradians       
Angular resolution        Tens of degrees (S1 vs. S2), tens of arcseconds (when used with multiple spacecraft)       

The PHA 1, 2, 3, 4 are used for the measurements of burst energy spectra in two energy ranges (A1 and A2) by means of 63 channel quasilog scale analyzers with an accumulation time varying from 64 ms to 8.192 s.

Energy                        Channel Width, keV
Range          1-17    18-26   27-34   35-38   39-44   45-49   50-50   60-63
10-770 keV     2.5     5.0     7.5     10      15      20      25      30
0.2-10 MeV     30      60      90      120     180     240     300     360

                       Prehistory          Time History                Total
Number of channel      257              256   2048    1024   511        4096 
Time resolution, ms    2                2     16      64     256
Time interval, s       0.514            0.512 32.768  65.536 130.816    230.146

The THA 1, 2, 3, 4 measure burst time histories in three energy ranges (SG1, SG2, and SG3) with a time resolution of 2 ms to 256 ms. All THA's are identical and their characteristics are given in the table above.

The HRTHA's are intended for measuring high intensity sections of a time history in three energy ranges (SG1, SG2, and SG3) with a 2-ms time resolution. Each such section is 0.128 s long. The instrument memory records the number of counts only in the last 62 and 64 intervals, i.e. during 0.122 s. The criterion for the recording to be made is that the number of counts of total length 7.808 s can be measured with high resolution in a burst.

The BM is designed for continuous measurements of the gamma- and cosmic-ray background. The count rates in four energy ranges (SG1, SG2, SG3, and SZ) are measured once each 8 minor frames. The accumulation time is 2.94 s if the telemetry rate is 5565 bps. Background measurements are interrupted only for the time required to read out the burst information.

The INTERBALL Mission and Payload

The INTERBALL project consists of two pairs of spacecraft aimed at the general study of the physical mechanisms responsible for the transport of solar wind energy to the Earth's magnetosphere, and its accumulation there, followed by dissipation in the auroral regions of the magnetosphere during substorms. The specific scientific objectives of the mission are to study active processes in the magnetospheric tail and their consequences in the auroral magnetosphere, such as:

The two pairs of spacecraft will be sent into very different orbits. One pair--the Auroral Probe--will be in an orbit from approximately 500 to 20,000 km at 65deg. inclination, crossing auroral field lines at 10,000 to 15,000 km. The other pair--the Tail Probe--will be in an orbit from approximately 500 to 200,000 km also with an inclination of 65deg., and crossing the plasma sheet at about 120,000 km. Each pair consists of a main Prognoz-type spacecraft accompanied by a subsatellite of the Magion type. The spacecraft will be spin stabilized with a nominal rate of 1/2 rpm. There will be data storage of 30 Mbit and 80 Mbit, respectively, and telemetry rates of 16, 40, and 64 kbps on each main spacecraft.

The subsatellites will have variable separations controlled by thrusters, up to 500 km for the Auroral Probe and up to 10,000 km for the Tail Probe. The subsatellites will use simple instruments to measure cold and hot plasmas, plasma waves, energetic particles, and magnetic and electric fields. The objectives for the subsatellites are to separate time and space variations, to study fine structures, and to search for spatial correlations. The launch is scheduled for 1992, with a nominal mission duration of one year.

The Auroral Probe will measure particle velocity distributions, magnetic and electric fields, plasma waves, and parameters of the cold plasma to study auroral particle acceleration and kilometric radiation mechanisms. It will also image the auroral oval to relate the above phenomena with the aurora. An on-board processor, reprogrammable from the ground, will organize the measurements.

The Tail Probe will carry fast (~10 sec) measurements of the 3-D particle velocity distribution, magnetic and electric fields, and plasma waves to study the plasma sheet dynamics during substorms. An on-board processor will recognize the signature of reconnection events and organize measurements. For example, a signature of the plasma sheet boundary connected with a reconnection site could be a low magnetic field (< 5 nT), rapid plasma flow (> 500 km/s), and bursts of energetic protons (~ 1 MeV). The Tail Probe will also carry one solar x-ray instrument.

The Auroral Probe

Auroral Plasma Experiments

SKA-3

Electron and proton spectrometer measures electron and ion distributions from 0.03 to 15 KeV, electron and ion anisotropies, ion masses of 1, 4, and 16 amu, and energy per charge from 30 to 500 KeV/Q. Mass: 32 kg, TM: 3 Kbps. A. Kuzmin and R. Kovrazhkin, IKI, Moscow, Russia.

ION

Ion spectrometer provides ion spectra and anisotropies for masses 1, 2, 4, 16 amu, and energy per charge from 0.005 to 20 KeV/Q. Mass: 17 kg, TM: 3 Kbps. J. A. Sauvaud, Centre d'études spatiales des rayonnements (CESR), Toulouse, France.

PROMICS-3

Electron and Ion Composition 3-D Spectrometer provides ion composition for 1 to 56 amu and energies per unit charge up to 100 KeV/Q. Mass: 13.5 kg, TM: 2 Kbps. I. Sandahl, Swedish Institute of Space Physics, Kiruna, Sweden. N. Pissarenko, E. Dubinin, IKI, Moscow, Russia. T. Pulkkinen, H. Koskinen, FMI, Helsinki, Finland.

Auroral Field Experiments

IMAP-3

Magnetometer provides 3 components of the magnetic field up to 60,000 nT with 1 nT resolution. Mass: 4.8 kg, TM: 1 Kbps. J. S. Archinkov, SDS Laboratories, Sofia, Bulgaria.

IESP-2

Electric Field Instrument provides electric field intensity at frequencies from 0 to 50 Hz. Mass: 6.7 kg, TM: 7.2 Kbps. G. Stanev, Central Laboratory for Space Research, Sofia, Bulgaria. V. Chmyrev, IZMIRAN, Troitsk-Moscow, Russia.

NVK-ONCH

VLF Receiver measures electromagnetic wave intensities from 20 Hz to 20 KHZ. Mass: 17 kg, TM: 2x12 KHZ transmitters. O. Molchanov and A. Goljavin, IZMIRAN, Moscow, Russia.

MEMO

Magnetic Wave Analyzer analyzes the wave spectrum of the magnetic field up to 2 Mhz. Mass: 14.5 kg, TM: 20 Kbps. F. Lefeuvre, Laboratoire de physique et chimie de l'environnement (LCPE), Orléans, France. M.M. Mogilevsky, IKI, Moscow, Russia.

POLRAD

Radio Receiver measures auroral kilometric radiation from 20 KHZ to 2 MHz. Mass: 22.5 kg, TM: 2.3 Kbps. J. Hanash and J. Juchniewicz, Space Research Center, Warsaw, Poland. N. Lishin, Institute of Radioelectronics, Moscow, Russia.

Thermal Plasma Experiments

HYPER-BOLOID

Ion Mass Analyzer analyzes low energy ions with energies from 0 to 100 eV, velocities from 0 to 20 km/s, and species: H+, He+, O+, O++, N+, N2+, NO+, and O2+. Mass: 15 kg, TM: 8 Kbps. J. J. Berthelier, Centre de recherche en physique de l'environnement terrestre et planétaire (CRPE), St. Maur des Fosses, France. T. Muliarchik, IKI, Moscow, Russia.

KM-7

Electron Temperature Probe measures electron temperatures up to 10 eV. Mass 2.7 kg, TM: 0.3 Kbps. J. Smilauer, Geophysical Institute, Prague, Czecho-Slovakia. V. Afonin, IKI, Moscow, Russia.

ALPHA-3

Ion Trap measures ion densities and energy distributions for densities above 1 per cm3 and energies to 25 eV. Mass: 3.5 kg, TM: 0.15 Kbps. V. V. Bezrukikh, IKI, Moscow.

RON

Ion Emitter emits nitrogen and indium ions to control the spacecraft potential. Emitted currents are from 1 to 10 microamp. Mass: 7.5 kg, TM: 0.2 Kbps. W. Riedler, Space Research Institute and Austrian Acadamy of Science, Graz, Austria. R. Schmidt, ESA/ESTEC, Noordwijk, Netherlands. Yi. I. Galperin, IKI, Moscow, Russia.

Energetic Particle Experiments

DOK-2A

Electron and proton spectrometer provides proton and electron energy spectra and anisotropies from 10 to 400 KeV (electrons) and 15 to 1000 KeV (protons). Mass: 5.5 kg, TM: 0.8 Kbps. K. Kudela, Inst. Exp Physics, Slovak Academy of Science, Kosice, Czecho-Slovakia. V. Lutsenko, IKI, Moscow, Russia. E. Sarris, University of Thrace, Xanthi, Greece.

Auroral Image Experiments

UFSIPS

UV Photometer measures emission intensities in the lines 1304 Angstroms (Å), 1356 Å and 1493 Å by scanning with the spacecraft rotation. Mass: 21 kg, TM 0.2 Kbps. K. Palazov, Space Research Institute, Bulgarian Academy of Science, Stara Zagora, Bulgaria. A. Kuzmin, IKI, Moscow, Russia.

UVAI

UV Auroral Imager obtains images of the aurora in the ultraviolet from 1400 Å to 1600 Å. Mass: 20 kg, TM: 3 Kbps. L. L. Cogger, Dept. of Physics, University of Calgary, Calgary, Canada. Yu. I. Galperin, IKI, Moscow, Russia.

Subsatellite for the Auroral Probe

C2-A

The subsatellite for the Auroral Probe has measurements of electric and magnetic fields, VLF waves, plasma and energetic particles. Mass: 50 kg, TM: 60 KHZ. P. Triska, Ya. Voita, Geophysics Institute, Czecho-Slovakia Academy of Science, Prague, Czecho-Slovakia. Yu. Agafonov, IKI, Moscow, Russia.

The Tail Probe

Plasma Experiments

SKA-1

3-D Ion Spectrometer measures ion energy and angular distributions from 0.1 to 5 KeV/Q. Ion Composition and Energy Spectra of H+, He++, He+, O+ from 5 to 50 KeV/Q. Mass: 26.1 kg, TM: 2 Kbps. O. Vaisberg and A. Leibov, IKI, Moscow, Russia.

VDP

3-D Sectorial Ion Faraday Cup measures the flux and direction of the solar wind and other flowing ion plasmas. Mass: 4.9 kg, TM: 1 Kbps. Ya. Shafrankova and Z. Nemechek, Department of Electrical and Vacuum Physics, Charles University, Prague, Czecho-Slovakia. G. Zastenker and A. Fedorov, IKI, Moscow, Russia.

ELECTRON

Electron Spectrometer will measure electron distribution functions from 0.01 to 30 KeV. Mass: 6.5 kg, TM: 1 Kbps. J. A. Sauvaud, Centre d'études spatiales des rayonnements (CESR), Toulouse, France. O. Vaisberg and N. Borodkova, IKI, Moscow, Russia.

CORALL

3-D Ion Spectrometer measures the ion distribution function from 0.1 to 30 KeV/Q. Mass: 5 kg, TM: 1 Kbps. R. Jimenez, Intercosmos, Havana, Cuba. L. Avanov and Yu. Yermolaev, IKI, Moscow, Russia.

AMEI-2

Ion Energy-Mass Analyzer measures ion composition and energy spectrum from 0.1 to 10 KeV/Q for masses 1 to 16 amu. Mass: 9 kg, TM: 0.2 Kbps. R. Koleva, Bulgarian Academy of Science, Solar-Terrestrial Influences Laboratory, Sofia, Bulgaria. V. Smirnov, IKI, Moscow, Russia.

MONITOR-3

Solar Wind Analyzer obtains the solar wind spectrum from 0.4 to 15 KeV/Q. Mass: 8 kg, TM: 8 Kbps. Z. Nemechek and Ya. Shafrankova, Department of Electronic and Vacuum Physics, Charles University, Prague, Czecho-Slovakia. A. Fedorov, IKI, Moscow, Russia.

PROMICS-3

Electron and Ion Composition 3-D Spectrometer provides ion composition for 1 to 56 amu and energies per unit charge up to 100 KeV/Q. Mass: 13.5 kg, TM: 2 Kbps. I. Sandahl, Swedish Institute of Space Physics, Kiruna, Sweden. N. Pissarenko, E. Dubinin, IKI, Moscow, Russia. T. Pulkkinen, H. Koskinen, FMI, Helsinki, Finland.

Thermal Plasma Experiment

ALFA-3

Ion Trap. ALFA-3 measures ion densities and energy distributions for densities above 1 per cm3 and energies to 25 eV. Mass: 3.5 kg, TM: 1 Kbps. V. V. Bezrukikh, IKI, Moscow.

Energetic Particles and X-Ray Experiments

SKA-2

Low and Energetic Charged Particle Experiment measures low and energetic charged particle composition and anisotropy: electron energy from 40 to 200 KeV; ion energy from 50 to 150 MeV. Mass: 22.4 kg; TM: 0.25 Kbps. E. Morozova, IKI, Moscow, Russia. S. Fisher, Astronomical Institute, Prague, Czecho-Slovakia. E. Sarris, University of Thrace, Xanthi, Greece.

DOK-2X

Electron and Proton Spectrometer obtains electron and proton fluxes and anisotropy: electron energy: 10 to 400 KeV; ion energy: 15 to 1000 KeV. Mass: 5.5 kg, TM: 2 Kbps. K. Kudela, Institute of Experimental Physics, Slovak Academy of Science, Kosice, Czecho-Slovakia. V. Lutsenko, IKI, Moscow, Russia. E. Sarris, University of Thrace, Xanthi, Greece.

RF-15

Solar X-Ray Instrument obtains the solar x-ray spectrum from 2 to 200 KeV. Mass: 10 kg, TM: 0.01 Kbps. F. Farnik, Astronomical Institute of Czecho-Slovakia, Ondrejov, Czecho-Slovakia. O. Likin, IKI, Moscow, Russia. A. Silvester, Vroclav Space Center, Poland.

Wave Complex ASPI

OPERA

Electric Field Instrument measures the electric field in the frequency range 0 to 250 KHZ. Mass: 3.7 kg, TM: 3 Kbps. E. Amata and V. Formisano, CNR/IFSI, Frascati, Italy. S. Savin and M. Nozdrachev, IKI, Moscow, Russia.

MIF-M

Magnetic Field Instrument measures the magnetic field in the frequency range 0 to 40 KHZ. Mass: 7.5 kg, TM: 2.5 Kbps. S. Romanov and M. Nozdrachev, IKI, Moscow, Russia.

IFPE

Ion and Electron Fluctuation Instrument measures ion and electron flux fluctuations in the frequency range from 0.1 to 1000 Hz. Mass: 4.9 kg, TM: 2.5 Kbps. J. Buchner, Max-Planck Institut für extraterrestriche Physik, Ausenstelle, Berlin, Germany. M. Nozdrachev, IKI, Moscow, Russia.

ADS

Multichannel Spectrum Analyzer obtains the frequency spectrum in the range from 0.25 Hz to 40 KHZ. Mass: 6.7 kg, TM: 1 Kbps. J. Juchniewicz and Z. Krawchek, Space Research Center, Polish Academy of Science, Warsaw, Poland. S. Romanov and A. Belikova, IKI, Moscow, Russia.

PRAM

Adaptive Processor processes wave information. Mass: 4 kg, TM: 4 Kbps. Ya. Stupka and S. Slaby, Czecho-Slovakia. N. Rybyeva and S. Romanov, IKI, Moscow, Russia.

IMAP-2

Magnetometer obtains the magnetic field up to 200 nT with a resolution of 0.05 nT. Mass: 4.9 kg, TM: 0.5 Kbps. J. S. Archinkov, SDS Laboratory, Sofia, Bulgaria. L. Zhuzgov, IZMIRAN, Troitsk, Moscow, Russia.

AKR-2

Radio Receiver receives kilometric radio emissions in the frequency range 100 KHZ to 1.5 MHz. Mass: 2.1 kg, TM: 1.8 Kbps. L. Fisher, Astronomical Institute, Prague, Czecho-Slovakia. V. Grigorieva, Astronomical Institute of Moscow State University, Moscow, Russia.

Subsatellite for the Tail Probe

C2-X

The subsatellite for the Tail Probe has measurements of electric and magnetic fields, VLF waves, plasma and energetic particles. Mass: 50 kg, TM: 20 KHZ. P. Triska and Ya. Voita, Geophysical Institute, Prague, Czecho-Slovakia. Yu. Agafonov, IKI, Moscow, Russia.

Key personnel for INTERBALL are:

Scientific Director:

Prof. Alec A. Galeev

Project Manager (Auroral Probe): R. A. Kovrazhkin

Project Manager (Tail Probe):

M. N. Nozdrachev

Project Scientist: Prof. Lev M. Zelenyi.