National Aeronautics and Space Administration

• Characterize the energetic space radiation environment and its interactions with spacecraft
• Provide data to other SET-1 experiments

Goals:

• Provide data to improve radiation environment models and design tools
• Demonstrate the value of a compact space weather monitor in operational spacecraft

Measurements:

• Proton flux > 40 MeV per unit solid angle
• Charge deposition in large silicon diodes arranged in telescopes. Pulse height analysis is used to obtain ion linear energy transfer (LET) spectra of heavy ions in the 100 MeV-cm2/g to 25000 MeV-cm2/g range
• Threshold voltage shift in MOS dosimeters to measure total ionizing dose at 2 different shielding depths
• Charging current at 3 different shielding depths to provide energetic electron flux measurements at 3 energies

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Dosimetry Intercomparison and Miniaturization Experiment (DIME)

PI: Dr. Peter McNulty, Clemson University

Objectives:

• Use five different COTS microdosimeters to characterize radiation induced total ionizing dose, displacement damage, and single event effects

Goals:

• Provide data to permit appropriate dosimetry selection in future missions to characterize/resolve operational anomalies
• Validate particle transport codes by varying shielding thicknesses on RADFETs

DIME Measurements:

• Threshold voltage shift of RADFETs as a function of time to obtain total ionizing dose
• Threshold voltage shift of erasable programmable read-only memories (EPROMs) as a function of time to obtain TID
• The number of single event upsets in EPROMs to determine the upset rates as a function of the radiation level;
• The pulse height spectra of two LET spectrometers as a function of time, one to determine the LET and hence energy spectrum of protons and the other to determine the LET of heavier ions
• The visible emission spectrum of optically-stimulated luminescent films to determine very low doses.

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Development of Space-Based Test Platform for the Characterization of Proton Effects and Enhanced Low Dose Rate Sensitivity (ELDRS) in Bipolar Junction Transistors

PI: Dr. Hugh Barnaby, Arizona State University

Objective:

• Measure ELDRS (primary) and proton effects (secondary) in positive-negative-positive (PNP) bipolar junction transistors (BJTs)

Goal:

• Improve understanding of the physics of ELDRS and thereby improve/validate ground test protocol for linear bipolar technologies and reduce design margins

Measurement:

• Base and collector currents for 24 COTS BJTs having different processing characteristics as a function of the emitter and gate voltages and time

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COTS-2: Digital Technologies

PI: Robert Ecoffet, CNES/France

Objective:

• Validate approaches to mitigate single event effects by comparing simulation techniques, performance models, and on-orbit data
• Validate mitigation of single event effects during space weather events

Goal:

• Increase reliability of COTS technologies for space applications and reduce design margins

Measurement:

• Measure single event effects on COTS FPGAs, classify the event by event type, and determine if mitigation of the effect occurred without watchdog intervention