**Appendix **

**I have tried to update to reflect a "Past Mission", instead of a
"Future Mission"**

**Needed: Summary of On-Orbit Operation**

** Some LBL results?**

**Table of Contents**

1\. INSTRUMENT PURPOSE

2\. EXPERIMENT OBJECTIVES

2.1 Primary

2.2 Secondary

3\. MEASUREMENT TECHNIQUE AND INSTRUMENT DESCRIPTION

3.1 General

3.2 Telescope Geometry

3.3 Detector Thresholds

3.4 Logic and Ground Commands

3.5 Telemetry

3.6 Isotope and Energy Ranges

4\. OPERATION IN MAGNETOSPHERE

5\. SCIENCE CALIBRATIONS

6\. STATUS AND PLANS

7\. REFERENCES

TABLES 1 THRU 7

FIGURES 1 THRU 11

**1. INSTRUMENT PURPOSE**

The purpose of the ONR-604 instrument was: a) to obtain new data on the
isotopic and elemental composition of high energy, heavy charged
particles which assist in understanding the high energy conversion
processes in solar flares, b) to discover observable solar conditions
leading up to the explosive phase of a solar flare, and c) to determine
the high energy, heavy ion fluxes in selected regions of the
magnetosphere in order to determine the importance of this component as
a source of radiation damage and \"soft upsets\" in electronic devices.

**2. EXPERIMENT OBJECTIVES**

* 2.1 Primary*

The primary objectives of this experiment were: (1) to study solar flare
energy conversion and high energy nuclear particle accelerator
mechanisms on the sun, (2) to monitor solar flare particle flux levels,
(3) to measure the high energy galactic cosmic ray distribution as a
\"template\" for solar flare observations, and (4) to determine the
composition of any heavy ions observed in the magnetosphere.

* 2.2 Secondary*

Secondary objectives include: (1) examination of constraints imposed on
stellar nucleosynthesis models and their application to the sun; (2)
determination of parameters for models or origin, acceleration, and
propagation of charged particles into the earth\'s magnetosphere; (3)
study of the access of solar particles into the earth\'s magnetosphere;
(4) determination of trapping times for particles observed in the
magnetosphere; and (5) space flight verification of the new technology
embodied in the solid-state position sensing detectors. (Ref. 1C)

**3. MEASUREMENT TECHNIQUE AND INSTRUMENT DESCRIPTION**

* 3.1 General*

Figure 1 shows a schematic cross-section of the charged particle
telescope. In order to achieve the high mass resolution needed for
isotopic separation of heavy ions, it was necessary to measure the
trajectory of each charged particle entering the acceptance cone of the
telescope, both to measure the pathlengths in the detectors and to
determine the arrival direction of the particles from space. This was
done using position-sensing detectors (PSD\'s) developed and fabricated
at the University and shown in Figure 2. As shown on the figure, these
detectors use a series of gold strips on the top surface of the detector
to collect the charge liberated by the passage of the particle. This
signal was read out through a resistive divider network and compared to
the total signal from the detector, obtained from the charge collected
on the back surface contact, to obtain one coordinate of the point of
incidence of the particle. Two sets of PSD\'s (three per set for
redundancy) were used in the telescope to obtain the trajectory of the
particle. Calibration of this system with accelerator particles shows
that the position can be measured to better than 0.1 mm and the angle of
incidence of the particle determined to better than 1°.

The charge and mass of each particle was determined by the well-known
technique of multiple dE/dx *vs* residual energy using the measurements
provided by the stack of 5 mm thick lithium drifted silicon detectors,
corrected for the trajectory of the individual particle. For this
analysis we require the particle to come to rest within the instrument,
which determines the energy range over which each type of particle can
be studied. As shown in Figure 1, the entire stack was surrounded by a
scintillator guard counter in anti-coincidence to eliminate
out-of-geometry events and to eliminate particles that exit from the
side of the apparatus. Further, a ground-commandable operations mode was
provided for the detailed analysis of proton and alpha particle flux
levels. Thus, complete measurements were obtained for any solar flare
observed.

In order to separate isotopes for elements as heavy as Nickel, it was
necessary to measure the dE/dx and residual energy signals to a
precision level of O.1%. This stringent constraint has been met by
developing exceptionally linear, highly stable electronic circuits to
analyze the signals from each detector. Each analysis chain was
individually calibrated, and the entire instrument performance has been
evaluated using high energy heavy ion beams obtained from the LBL
Bevalac accelerator.

The performance of each analysis chain was monitored during flight by an
on-board calibrator which sends a sequence of 2000 pulses spanning the
entire range of signal sizes. Furthermore, in-flight calibration and
normalization was provided by measurement of galactic cosmic ray events.
These high precision measurements require that a) the temperature remain
stable and constant to within \~3°C over the orbit and b) consequently
the instrument power was on during 100% of the orbital period.

Because the anti-coincidence scintillator guard counter subtends a large
solid angle and was used in the instrument logic, it must be shielded
from the high counting rates induced by electrons trapped in the
magnetosphere. The shielding is shown in Figure 3 and corresponds to
complete elimination of \< 4 MeV electrons by the AZ31B magnesium shield
and the Tantalum collar. The lower part of the scintillator was located
well within the instrument package and was surrounded on five sides by
electronic modules which offer additional shielding. The backward moving
particles were shielded additionally by the spacecraft structure.

Since a three-year mission was planned, in order to protect further
against accumulated radiation damage to the detectors Dl, D2 and D3
(where the average geometrical factor was 87 cm^2^-ster), a 3mm external
Al window shield was placed over the telescope. This shield lowers the
magnetospheric integrated proton and electron radiation doses for
detectors Dl, D2, D3 below the tolerance threshold of these detectors
while moving upwards only slightly the energy intervals for measurement
of the heavy particles, which were the main objective of the experiment.

In addition to heavy particles the instrument measured protons and alpha
particles over the energy range 25-119 MeV. In quiet regions of space, a
priority system insured that the heavy nuclei were analyzed in
preference to protons and alphas. In regions of high background
radiation, a commandable heavy particle \"normal mode\" was invoked.
This raises the thresholds on the detectors D1 through D6 to suppress
the high firing rates induced by trapped protons and electrons while
still permitting the rare heavy ions to be analyzed.

Figure 4 shows a functional block diagram of the instrument electronics.
Besides providing the measurement of pulse height analysis, the
instrument had internal accumulators that counted and stored both single
detector counting rates and coincidence counting rates, thus allowing
the absolute sampling rate and the absolute flux levels to be deduced. A
priority system ensured that the rare events were preferentially
analyzed and stored. A ground commandable operations mode was provided
for the detailed analysis of proton and alpha particle flux levels.

Table 1 gives a summary of ONR-604's vital statistics.

* 3.2 Telescope Geometry*

Table 2 gives a summary of telescope geometry data relevant to the
measurement of fluxes and the analysis of pulse heights of energetic
charged particles. The Table gives Dl and the given detector (to top and
bottom), the relevant geometrical factors through the window, and the
proton energy needed at 0° to penetrate the detectors (see Figure 1).

The highest quality isotopic data was obtained for particles stopping in
K2 and below. However, the telescope can also measure particles:

a\) stopping in K1

b\) stopping in D2 - D6

c\) penetrating K8

For a) and b) it was necessary to use the signal from the E contact of
the PSDs to provide energy loss information. For events stopping in D2
or D3, the pathlength uncertainty was given by sec Q where Q was the
maximum angle through the window (69° for D2 which gives a spread of a
factor of 2.8). Thus, D1D2D3 analysis can separate protons and helium,
but no heavier elements. For particles stopping in D4, the sec Q spread
was reduced to a factor of 1.44.

For particles stopping in D5 - K1, there was trajectory information
available and elemental separation was limited only by the quality of
the E signals from the PSDs \-- in fact there was even some isotopic
capability for these events. Finally, the chemical composition of events
penetrating the entire stack can be studied over a limited energy
interval.

* 3.3 Detector Thresholds*

Table 3 lists the ONR-604 detector thresholds in \"normal mode\" and in
\"proton mode\". In \"normal mode\" the \"proton mode\" thresholds of
detectors Dl

through D6 were increased by a factor 5.8 and as a consequence the
instrument becomes insensitive to protons.

* 3.4 Logic and Ground Commands*

Table 4 describes the rate logic and the incident energy intervals for
representative energetic particles. Table 5 gives the logic for the
pulse height analysis gate control and analysis priorities, and the
ground commands and their action on the logic.

* 3 .5 Telemetry*

Figure 5 shows the CRRES minor telemetry frame with the location of the
12 8-bit words allocated to ONR-604. 360-bit blocks from ONR-604 were
loaded into a first-in first-out (FIFO) register. The contents of FIFO
were read out into the downlink in 8-bit words in 4 minor frames or
0.512 sec (0.128 sec/frame).

The number of bits read out into the downlink was 384 (360 bits of
instrument data plus 24 fill bits). The overall bit rate of ONR-604 was
750 bits/second.

* 3.6 Isotope and Energy Ranges*

Figure 6 shows the incident kinetic energy intervals in the telescope
corresponding to detector penetration ranges (essentially equal to the
energies triggering the low thresholds in \"proton mode\") for isotopes
H^1^ through Ni^59^. For every isotope the inclined lines connect the
points for zero incidence angle (bottom) with the points at 30°
incidence angle (top).

**4. OPERATION IN THE MAGNETOSPHERE**

Table 6 gives the coverage time for the measurement of various isotopes.
This coverage time was the fraction of the CRRES orbital period of the
final orbit with Stormer cutoff within or below the ONR-604 sensitive
energy range.

The coverage time is given as a function of the index of the particle
differential energy spectra assumed to be a power law in energy (i.e. µ
E^+g^).

Table 7 gives an estimate of the expected counting rates in proton mode
for an incident high intensity hard spectrum of trapped protons like the
P-4

spectrum present in the South Atlantic Anomaly^\ (^M.J. Teague et al.,
NSSDC Report 72-11, November 1982 and 74-03, April 1974.)

.

**5. SCIENCE CALIBRATIONS (PRE-FLIGHT)**

The ONR-604 instrument was calibrated in July 1977, April 1978 and July
1979 with beams of C, Ne, Ar and Fe particles (with energies such that
the particles stopped in the telescope) accelerated at the
Bevatron/Bevalac of the Lawrence Radiation Laboratory.

A final calibration of ONR-604 was carried out at this facility before
the initial instrument delivery for integration in 1985. This
calibration included proton and helium nuclei.

Because of the long postponement of the CRRES mission after the
Challenger accident, a second "final" calibration was performed at the
same facility in February 1989, after replacement of most of ONR-604's
detectors.

After integration with the XXX spacecraft, in addition to test
procedures, there was a m-meson calibration at: a) the integration site
and b) at the Kennedy Space Center. Each calibration required more than
48 hours of running time. A typical m-meson calibration obtained with a
telescope similar to ONR-604 is shown in Figure 7.

**6. ON-ORBIT OPERATION**

TBD

**7. REFERENCES (Needs to be redone, or else folded into non-appendix
reference)**

A.

1A. \"The Composition, Propagation and Acceleration of Energetic Solar
Particles: A Review of United States Research 1979-1982\", R.E. McGuire,
, 21, 305, 1983.

2A. \"Spacecraft Measurements of the Elemental and Isotopic Composition
of Solar Energetic Particles\", R.A. Mewaldt , ed. R.0. Pepin, J.A. Eddy
and R.B. Merril, pp. 81-101, 1980.

3A. \"Elemental and Isotopic Composition of the Galactic Cosmic Rays\",
J.A. Simpson, , 33, 33, 1983.

B.

1B.\"Cosmic Ray Effects on Microelectronics, Part I: The Near-Earth
Particle Environment\" J.H. Adams Jr., R. Silberberg and C.H. Tsao,

2B. \"The Isotopic and Elemental Abundances of Neon Nuclei Accelerated
in Solar Flares\", W.F. Dietrich and J.A. Simpson, , L91, 1979.

3B.\"The Isotopic Composition of Magnesium Nuclei in Solar Flares\",
W.F. Dietrich and J.A. Simpson, , , L41, 1981.

4B.\"Super Enrichments of Fe-Group Nuclei in Solar Flares and their
Association with large ^3^He Enrichments\", J.D. Anglin, W.F. Dietrich
and J.A. Simpson, Proc. 15th Int. Cosmic Ray Conf., Plovdiv, , 43, 1977.

C.

1C. \"A Large Area Circular Position Sensitive Si Detector\", J.E.
Lamport, G.M. Mason, M.A. Perkins and A.J. Tuzzolino, Nuclear Instr. and
Methods, , 71, 1976.

2C. \"ONR-604 Annex\" of February 1983 (unpublished).

TABLE 1

ONR-604 VITAL STATISTICS

[\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_]{.underline}

Weight 32 (+1, -0) lbs.

Volume: Package & Telescope 12.0 x 17.0 x 11.75 in.

Viewing: a) Direction Telescope Axis Normal to S/C Spin Axis

b\) Cone (Unobstructed) 93° (Full Angle)

Geometrical Factor 90 to 3 cm^2^ ster

Power 6.0 Watts, Average; \<8.0 Watts, Peak

Bit Rate 360 Bits/Readout (0.512 sec readout)

750 b/s at Interface

Operating Duty Cycle 100%

Ground Commands 2 Power, 12 Mode (Command Word)

Calibration and Testing Through Test Connector -

(Pre-Launch)/(Post-Launch) IFC Source - Onboard - IFC/Data^\*^

Environmental: Temperature -10°C to \~10°C with \< 3°C

Variation/Orbit

Chemical Not To Be Exposed to Solvent

(Because of Solid-State

Detectors)

Humidity Relative Humidity \< 55%:

Dry Air Purging

Energy Range (Isotopes) 25-570 MeV/Nucleon

Charge Range For Isotopic Separation Hydrogen to Nickel

Mass Resolution At Iron s » 0.22 AMU

Science Calibration Performed With Heavy Ion Beams

at the Bevalac Accelerator of the

Lawrence Berkeley Laboratory

Critical Requirements a) Dry air purge of instrument

(Ref. 2C)

b\) Standby bias applied to solid

state detectors when instrument

power was off (Ref. 2C)

^\*\ ^IFC = Inflight Calibrator

**TABLE 2**

Detector qm from D1 to: Geometrical Factor (cm^2^-ster) Ep (MeV)

to penetrate to

Top Bottom Top Bottom bottom of detector

Window - - 379.4 379.4 -

Dl - - 95.0 93.6 28.3

D2 87.10 - 87.9 86.6 31.7

D3 84.1 - 81.3 80.0 35.1

D4 50.0 - 16.2 16.3 36.6

D5 47.9 - 14.9 14.9 38.5

D6 46.0 - 13.6 13.7 40.0

K1 41.3 39.2 8.2 7.5 52.0

K2 38.6 36.7 7.0 6.4 62.1

K3 36.1 34.4 6.0 5.5 71.2

K4 33.9 32.4 5.2 4.8 79.3

K5 32.0 30.6 4.4 4.1 87.0

K6 30.2 28.9 3.9 3.6 94.0

K7 28.6 27.4 3.4 3.2 100.8

K8 27.1 26.1 3.0 2.8 107.5

A - - 3.0 2.8 108.5

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

Note the large geometrical factor for events in D1, D2 and D3.

TABLE 3

ONR-604 DETECTOR THRESHOLDS (MeV)

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

[Detector]{.underline} [Normal Mode]{.underline} [Proton
Mode]{.underline}

Dl 4.45 0.77

D2 4.53 0.78

D3 4.55 0.78

D4 1.65 0.28

D5 1.71 0.29

D6 1.69 0.29

[Normal Mode and Proton Mode]{.underline}

[Low]{.underline} [Medium]{.underline} [High]{.underline}

Kl 0.693 36.9 1205

K2 0.647 37.9 1082

K3 0.653 - 1199

K4 0.654 - 1197

K5 0.668 - 1197

K6 0.649 - 1201

K7 0.680 - 1209

K8 0.664 - 1194

A 0.214 - -

TABLE 4

^\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_^

Rate No. Detector Rate Logic Energy Interval Particle Interval of Rate
In Defining

Proton Mode Rate Interval

(MeV)

^\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_^

\_\_\_\_

1 D1 D1D2D3 (S)a 24.8- 44.5 Protons

\_\_\_\_

2 D2 D1D2D3D4 (S)a 28.3- 48.2 \"

\_\_\_\_

3 D4 D13D4D5D6 (S)a 35.1- 43.9 \"

\_\_\_\_

4 D5 D13D5D6K1 (S)a 36.6- 45.5 \"

\_\_\_

5 K1 D13K1K2K3 (S)a 40.0- 59.4 \"

\_\_

6 K2 D13K1K2K3 (S)a 52.0- 70.6 \"

\_

7 K3 D13K1K3K4 (S)a 62.1- 79.9 \"

\_\_

8 K4 D13K1K4K5 (S)a 71.2- 88.5 \"

\_\_

9 K5 D13K1K5K6 (S)a 79.3- 96.5 \"

\_\_

10 K6 D13K1K6K7 (S)a 87.0-103.5 \"

\_

11 K7K8 D13K1K7A (S)a 94.0-116.9 \"

12 A D13K1K8A (S)a 107.5-275 \"

13 P3 D13S+D13 (K1+K2)24.8-275 \"

\_

14 P2 P3 (K1M+K2M)A 42-105 He^4^

15 P1 P3 (K1H+K2H+

K3H+K4H+

K5H+K6H+K8H)127-352 Mg^24^

16 Single Detector Rates

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

Notes: M Medium Threshold; H High Threshold

(Low Threshold was indicated by detector symbol not followed by M or H

S Scintillation guard counter.

(S)a S term included every alternate readout.

P3 Pulse Height Analysis Gate Control (Priority No. 3 or low

priority).

P2 Priority No. 2 or Medium Priority

P1 Priority No. 1 or High Priority

TABLE 5

ONR-604 PULSE HEIGHT ANALYSIS GATE CONTROL AND PRIORITY LOGIC,

AND GROUND COMMAND

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

\_

Gate Control GC = D1D2D3S + D1D2D3 (K1 + K2)

Priority 3 (Low Priority) P3 = GC

\_

Priority 2 (Medium Priority) P2 = GC (K1M + K2M) A

Priority 1 (High Priority) P1 = GC (K1H + K2H + K3H + K4H + K5H + K6H +

K7H + K8H

Ground Commands 16 Bit Serial Digital Command Word

[Bit No. (In Order Received)]{.underline} [Function]{.underline}

1 Start Calibrate Sequence

2 Override Calibrate

3 Disable Dl

4 Disable D2

5 Disable D3

6 Disable K1

7 Disable K2

8 Disable A

9 Disable S

10 Inhibit P2

11 Inhibit P3

12 Set Proton Mode

13-16 Spares

TABLE 6

ONR-604 ISOTOPE COVERAGE TIME

(Fraction of Orbital Period)

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

[Isotope]{.underline} [Spectral Power-Law Indices ( )]{.underline}

-6 -3 +1

He^3^ 0.23 0.31 0.47

He^4^ 0.47 0.51 0.60

O^16^ 0.47 0.51 0.60

O^18^ 0.53 0.56 0.64

Ne^20^ 0.47 0.51 0.60

Ne^22^ 0.52 0.55 0.63

Ar^36^ 0.47 0.51 0.60

Ar^40^ 0.52 0.56 0.64

Fe^54^ 0.49 0.53 0.62

Fe^56^ 0.51 0.54 0.63

TABLE 7

ONR-604 TRAPPED PROTON COUNTING RATES

(Given For a P-4 Trapped Proton Spectrum)

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

[Rate No.]{.underline} [Detector Interval]{.underline} [Proton Energy
Range]{.underline} [Counts/Second]{.underline}

(MeV)

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

1 D1 25- 45 1.8 x 10^5^

2 D2 28- 48 1.4 x 10^4^

3 D4 35- 44 1300

4 D5 37- 46 860

5 K1 40- 59 1000

6 K2 52- 71 500

7 K3 62- 80 270

8 K4 71- 89 270

9 K5 79- 97 240

10 K6 87-104 100

11 K7K8 94-117 200

12 A 108-275 900

13 P3 Logic Normalization Rate

14 P2 Logic Normalization Rate

15 P1 Logic Normalization Rate

16 Subcommutated Single Rates