Energetic Charged Particle Spectrometer for the Space Environment Reliability Verification Integrated System (SERVIS-1) Satellite

Transcription

1 VG Energetic Charged Particle Spectrometer for the Space Environment Reliability Verification Integrated System (SERVIS-1) Satellite G.E. Galica, 1 B.D. Green, 1 T. Nakamura, 1 H. Hasegawa, 2 T. Itoh, 2 and Y. Sasaki, 2 H. Kanai, 3 M. Akiyama, 3 and K. Hama 3 1 Physical Sciences Inc. 2 Mitsubishi Precision Co., Ltd. 3 Institute for Unmanned Space Experiment Free Flyer IEEE Nuclear and Space Radiation Effects Conference July 2004 Physical Sciences Inc. 20 New England Business Center Andover, MA 01810

2 Abstract VG We present the design and results from a new radiation sensor, the Light Particle Detector, designed specifically to quantify the orbital environment responsible for microelectronics damage. It supports Japan s Space Environment Reliability Verification Integrated System.

3 SERVIS Space Environment Reliability Verification Integrated System VG A program with two spacecraft to validate the use of commercial electronics in orbit better performance lower cost faster delivery Environment diagnostic instrument suite LPD PSI charged particle spectrometer dosimeters SERVIS-1 launched in late 2003

4 SERVIS-1 Satellite Launch VG ROKET launcher (SS-19) Plesetsk, Russia 30 Oct 2003, 1343 UT 997 km polar orbit deg inclination

5 LPD Light Particle Detector Designed for and manifested on the SERVIS-1 satellite (Japan) Built for Mitsubishi Precision Corp. Space Environment Reliability Verification Integrated System Launch Fall 2003 SERVIS-2 follow-on launch 2005 Energy Range Protons: MeV (6 bins) Electrons: MeV (4 bins) Alphas: >12 MeV (1 bin) Ions: >3 MeV/nucleon (1bin) Large G-factor/high count rate 0.2 cm 2 sr 200 kcps Physical parameters 4 kg (fully redundant) 7 W (HiRel/RadHard) VG

6 LPD Spectrometer Block Diagram Energetic particles deposit energy in SSD and Scintillator as they pass through By analyzing the detector signals, LPD identifies particle type and energy LPD increments a one of 12 particle-energy bins that represent the orbital distribution Only the spectrum is downloaded to the ground (60,000-fold compression) VG HV HV Energy deposited in SSD & Scintillator Window p+, e-, a, h Scintillator Collimator SSD Shielding PMT PA Calibration Pulse Discriminator/ Multilevel Comparator Electronics RS422 I/F DAE +5V ±15V DAE Change-Sensitive PA Bin Counters E-3907cz

7 Redundancy As bus component, LPD is required to be fully redundant LPD cannot be susceptible to single point failure Redundancy approach 2 stacked SSDs 1 scintillator 2 PMTs 2 preamp pairs 2 bias supply pairs 2 processing electronics Side A and B do not have identical performance (low energy protons), but offers full redundancy Scint PMT B EMSS I/F VG SSD PA A Electronics EMSS I/F E-5340

8 GEANT Sensor Model VG We developed a sensor model using the GEANT code - no free parameters The model is validated with calibration data We use the model to: develop and refine the sensor and algorithm design interpolate/extrapolate sensor response to uncalibrated regimes predict on-orbit performance 2001/01/ Servis (0.05/0.05/2.4) e/p/alpha/oxygen 2001/01/ Servis (0.05/0.05/2.4) e/p/alpha/oxygen 10 2 Ssd > Ssinsig < Ssd2 > Ssinsig < Ssd1, MeV 10 SSD Ssd2, MeV 10 Scintillator Epart, MeV E Epart, MeV E-8757

9 LPD Sensor Model Examples VG

10 Bin Performance - Protons PSI uses a combination of calibration data and a validated Monte-Carlo sensor model to refine the LPD logic and to predict bin performance VG Low energy Servis (0.05/0.05/2.4) p 2001/01/ High energy Servis (0.05/0.05/2.4) p 2001/01/ Fractional Response P1P2 P3 P4 SSD > 0.07 Proton Band SCINSIG > P5 Fractional Response > SSD > 0.25 Proton Band SCINSIG > P5 P Incident Energy, MeV E-8754a Incident Energy, MeV E-8755a

11 Bin Performance - Electrons PSI uses a combination of calibration data and a validated Monte-Carlo sensor model to refine the LPD logic and to predict bin performance Servis (0.05/0.05/2.4)e 2001/01/ VG Fractional Response e4 e3 e2 e1 e5 SSD > Electron Band SCINSIG > Incident Energy, MeV E-8753a

12 SERVIS-1 LPD Bins VG A B Energy Range (FWHM) Energy Range (FWHM) Bin Low (Mev) High (Mev) G-factor (cm 2 sr) Low (MeV) High (MeV) G-factor (cm 2 sr) E E E E4 6.6 > > P P P P P P A H 2 MeV/nucl 160 MeV/nucl MeV/nucl 160 MeV/nucl 0.26

13 Proton Calibration energy deposited (MeV) Proton SSD-A response GEANT data proton energy (MeV) VG Proton calibrations performed at Harvard Cyclotron Lab and at Indiana University CF HCL MeV IUCF MeV LPD meets its requirement to detect 150 MeV protons energy deposited (MeV) GEANT data Proton Scintillator Response proton energy (MeV) Linear response of SSD SSD and scintillator responses match sensor model predictions

14 Electron Calibration signal (volts) SERVIS LPD SSDA - electron signals SSDA fit energy deposited (MeV) VG Electron calibrations performed at NIST, Gaithersburg, MD Van de Graaf MeV Cascading Rheostat MeV LPD meets its requirement to detect 300 kev electrons 6.E+05 SERVIS LPD SSDA kev electron Linear response of SSD number/bin 4.E+05 2.E+05 SSD performance matches model predictions 0.E signal (volts)

15 LPD Performance Parameters VG de/e (fwhm) relative response resolution vs. angle - 55 MeV proton angle (degrees) SERVIS-1 LPD Acceptance Angle predicted measured angle (degrees) Large acceptance angle required to meet mission goals ±20 deg FWHM ±30 deg acceptance cone G = 0.2 cm 2 sr High count rate capability required to accommodate large acceptance angle 200 kcps Inherent energy resolution of 0.15 de/e even with large acceptance angle

16 SERVIS-1 Orbit and Radiation Environment 1000 km altitude into the bottom of the van Allen proton belts (650 to 6500 km) VG deg inclination polar orbit passes though the auroral region magnetic field lines intersect the Earth South Atlantic Anomaly (SAA) Earth's magnetic field is not aligned with geographic coordinates offset from Earth s center and tilted wrt to true north SAA is a region in the South Atlantic where the Earth s magnetic field is closer to the Earth s surface SERVIS1 travels N-S around the Earth and passes through the auroral ring and the SAA

17 Electron Distribution Auroral zone VG SAA Auroral zone

18 Proton Distribution Protons primary contribution in SAA Electrons contributions from SAA and Auroral zone VG Auroral zone SAA Auroral zone

19 LPD Proton Data vs AP8 Model Proton data maps out the SAA Measured flux rates are higher than model predictions (3-4x) LPD data can be used to update orbital flux models VG flux (cm-2 sec-1) 1.E+07 1.E+06 1.E+05 1.E+04 1.E+03 1.E+02 proton data (1 Dec 03) P MeV P MeV P MeV P MeV P MeV P MeV 1.E+01 7:59:20 9:16:48 10:34:12 11:51:36 13:09:00 14:26:24 15:43:47 17:01:11 18:18:35 19:36:03 20:53:27 22:10:51 23:28:15 0:45:39 2:03:02 3:20:26 4:37:50 5:55:14 UT (hh:mm:ss)

20 LPD Electron Data vs AE8 Model VG Measured flux rates are only slightly higher than model predictions LPD data can be used to update orbital flux models Level of detail (spatial structure) in the data far exceeds the model electron data (1 Dec 03) 1.E+08 1.E+07 E MeV E MeV E MeV E4 >6.6 MeV flux (cm-2 sec-1) 1.E+06 1.E+05 1.E+04 1.E+03 1.E+02 1.E+01 7:59:20 9:15:52 10:32:20 11:48:48 13:05:16 14:21:44 15:38:11 16:54:39 18:11:07 19:27:39 20:44:07 22:00:35 23:17:03 0:33:31 1:49:58 3:06:26 4:22:54 5:39:22 6:55:50 UT (hh:mm:ss)

21 SERVIS LPD - Proton Data Auroral Ring - N SAA Auroral Ring - S VG SAA dominates proton flux Auroral ring is small and spatially small Primarily low energy protons in Auroral zone High energy protons in SAA 1.0E E+06 Measured Trapped Proton Data 2 Dec 03 p M ev p MeV p MeV p MeV p MeV p MeV Proton Flux (cm-2 s-1) 1.0E E E E E+01 8:00 10:00 12:00 14:00 16:00 UT (hh:mm)

22 SERVIS LPD Electron Data Auroral Zone - N SAA Auroral Zone - S VG Auroral electrons large contribution Auroral ring large and structured High energy electrons in SAA 1.0E E+07 Measured Trapped Electron Data 2 Dec 03 e M ev e M ev e MeV e4 -- >6.6 M ev Electron Flux (cm-2 s-1) 1.0E E E E E E+01 8:00 10:00 12:00 14:00 16:00 UT (hh:mm)

23 Solar Storms Coronal Mass Ejections (CMEs) large ejections of energetic material from the sun solar wind accelerates as it approaches the Earth CMEs significantly distort the Earth's magnetic field inject high energy particles into the lower magnetosphere enhance the aurora VG

24 Late Oct 03 Aurorae VG Very strong CMEs in Fall 2003 Strong aurorae visible very far south Boston New York Carolinas SERVIS-1 launched on 30 Oct missed the initial CME however LPD detected the follow-on activity 1 solar rotation period later

25 GOES Satellite Protons (26 Oct Nov 03) VG

26 SERVIS LPD 2 Dec 03 On 2 Dec 2003, SERVIS LPD detected a sudden, spatially distinct enhancement of lowenergy protons VG Low energy protons (1-12 MeV) enhanced first Enhancement in higher energy protons (12-25 MeV; MeV) occurred after a delay No discernable activity in electrons SAA proton flux was also enhanced

27 Proton Flux Enhancement Persistent for Several Days p M ev Measured Trapped Proton Data p M ev 2 Dec 3 Dec 2 Dec 03 p M ev 1.0E E E+06 p MeV p MeV p MeV 1.0E+06 Measured Trapped Proton Data 3 Dec 03 VG p M ev p M ev p M ev p M ev p MeV p M ev Proton Flux (cm-2 s-1) 1.0E E E E+02 Proton Flux (cm-2 s-1) 1.0E E E E E+01 7:00 9:00 11:00 13:00 15:00 17:00 19:00 21:00 23:00 UT (hh:mm) 1.0E+01 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 0:00 UT (hh:mm) 1.0E E+06 4 Dec Measured Trapped Proton Data 4 Dec 03 p M ev p M ev p M ev p MeV p MeV p M ev 1.0E E+06 5 Dec Measured Trapped Proton Data 5 Dec 03 p M ev p M ev p M ev p MeV p MeV p M ev Proton Flux (cm-2 s-1) 1.0E E E E+02 Proton Flux (cm-2 s-1) 1.0E E E E E+01 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 0:00 UT (hh:mm) 1.0E+01 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 0:00 UT (hh:mm)

28 GOES Proton Data 1-7 Dec 03 VG GOES also detected enhanced proton flux simultaneously Same delay between low and high energy proton enhancement GOES satellite in geosynchronous orbit

29 Proton Enhancement Time History VG Low-energy proton flux rose suddenly (within hours) and decayed over several days Higher energy protons exhibited quick initial decay, but longer secondary decay 1.E+05 Temporal History of Proton Storm 1.E MeV MeV MeV Counts 1.E+03 1.E+02 1.E+01 1.E Time (hrs)

30 Spatial Distribution of Enhancement Enhancement is occurring within the auroral ring at the north and south poles Structure is present within the polar regions VG E+07 SAA Proton Flux (cm-2 s-1) 1.E+06 1.E+05 1.E+04 1.E+03 1.E+02 auroral ring - auroral ring - north pole south pole 1.E+01 8:00 10:00 12:00 14:00 16:00 UT (hh:mm)

31 Electron Activity VG Electron activity is not as distinct Possible spatial distortions in SAA Possible enhancement and spatial structure at poles 1.0E+08 e MeV 2 Dec Measured Trapped Electron Data e MeV 3 Dec 2 Dec 03 e MeV 1.0E+08 e4 -- >6.6 MeV Measured Trapped Electron Data 2 Dec 03 e MeV e MeV e MeV e4 -- >6.6 MeV Electron Flux (cm-2 s-1) 1.0E E E E E E E+01 8:00 10:00 12:00 14:00 16:00 UT (hh:mm) Electron Flux (cm-2 s-1) 1.0E E E E E E E+01 16:00 18:00 20:00 22:00 0:00 UT (hh:mm)

32 GOES Electrons VG GOES electron data quiet on 2-5 Dec Electron activity observed on 5-7 Dec

33 SERVIS Electron Data 1/2 1.0E+08 2 Dec Measured Trapped Electron Data 2 Dec 03 e MeV e MeV e MeV e4 -- >6.6 M ev 1.0E+08 3 Dec Measured Trapped Electron Data 3 Dec 03 VG e MeV e MeV e MeV e4 -- >6.6 M ev 1.0E E+07 Electron Flux (cm-2 s-1) 1.0E E E E E+02 Electron Flux (cm-2 s-1) 1.0E E E E E E+01 7:00 9:00 11:00 13:00 15:00 17:00 19:00 21:00 23:00 UT (hh:mm) 1.0E+01 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 0:00 UT (hh:mm) e MeV Measured Trapped Electron Data e MeV 4 Dec 5 Dec 4 Dec 03 e MeV 1.0E E+08 e4 -- >6.6 M ev Measured Trapped Electron Data 5 Dec 03 e MeV e MeV e MeV e4 -- >6.6 M ev 1.0E E+07 Electron Flux (cm-2 s-1) 1.0E E E E E+02 Electron Flux (cm-2 s-1) 1.0E E E E E E+01 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 0:00 UT (hh:mm) 1.0E+01 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 0:00 UT (hh:mm)

34 SERVIS Electron Data 2/2 VG e MeV 6 Dec Measured Trapped Electron Data e M ev 7 Dec 6 Dec 03 e MeV 1.0E E+08 e4 -- >6.6 M ev Measured Trapped Electron Data 7 Dec 03 e MeV e MeV e MeV e4 -- >6.6 M ev 1.0E E+07 Electron Flux (cm-2 s-1) 1.0E E E E E+02 Electron Flux (cm-2 s-1) 1.0E E E E E E+01 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 0:00 UT (hh:mm) 1.0E+01 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 0:00 UT (hh:mm)

35 Summary and Conclusions VG SERVIS-1 LPD has several performance goals that have now been demonstrated on orbit: Single sensor to detect protons, electrons, alphas, heavy ions Large throughput (AΩ) results in high count rates, efficient detection of small populations of particles, good counting statistics High count rate does not saturate during solar storms Good particle discrimination misassignment of low energy electrons as low energy protons is a chronic problem with most flight sensor designs electrons outnumber protons by 10x to >100x proton channels often get hosed achieving 10-3 or 10-4 contamination High accuracy calibration and validated sensor model returning fully calibrated data from sensor turn-on PSI (LPD & SDOM) sensors are now returning the high-quality on-orbit radiation data