DOSTEL Dosimetry Measurements Aboard ISS

1. S. Burmeister1, R. Beaujean1 , T. Berger2 , G. Reitz2 1 Universität Kiel/IEAP, 24098 Kiel, Germany 2 DLR Köln/Flugmedizin, 51147 Köln, Germany DOSTEL Dosimetry Measurements Aboard ISS

2. DOSTEL Detector Head The DOSTEL Detecor Head consists two circular PIPS detectors by Canberra. These two are forming a telescope with an opening angle of 120°. The active area of the PIPS detectors is 6.93 cm².

3. DOSTEL • DOSTEL can provide count rate profiles, dose rate profiles and energy deposit spectra • The energy spectra can be used to obtain LET-Spectra because of the path length limitation due to its telescope geometry • The LET spectra can be used to get information such as average quality factors which leads to dose equivalent

4. DOSMAP DOSTEL

5. DOSMAP DOSTEL

6. DOSMAP DOSTEL Data

7. Easter Event 2001

8. Easter Event 2001

9. Count Rate Mapping

10. DOSTEL Data Analysis • For further analysis the contribution of the GCR component should be seperated from the contribution of the SAA component • DOSTEL integrates the spectra over half orbits starting new integration periods near the cosmic ray equator. DOSTEL automatically finds these count rate minima by comparision to the last half orbit • For the GCR spectra only the northern half orbits where used to be sure to get rid of SAA contributions • An automatic S/W was used to separate these northern half orbits

11. DOSTEL Data Analysis

12. DOSTEL Data Analysis

13. DOSTEL Data Analysis

14. DOSTEL Data Analysis

15. MATROSHKA DOSTEL

16. MATROSHKA DOSTEL The DOSTEL Detecor Head consists two circular PIPS detectors by Canberra. These two are forming a telescope. Two perpendicular mounted Hamamatsu PIN-diodes are used as ‚stand-alone‘ dosimeters. The active area of the PIPS detectors is 6.93 cm², the PIN-diodes have an active area of 2.31 cm² each. by Hamamatsu

17. MATROSHKA DOSTEL Power- and signal-connection to Electronics Box Canberra PIPS (behind Kapton cover) Charge sensitive amplifiers Hamamatsu PIN

18. MATROSHKA DOSTEL Block Diagram of DOSTEL Electronics DOSTEL

19. Overview of MATROSHKA DOSTELsTrigger Rate At the time when any of the detectors receives a signal, the signal processing will be initiated. The count rate of these events is shown in the picture. One can also see the active time of DOSTEL or the time we got data for respectively.

20. MATROSHKA DOSTELData Analysis

22. MATROSHKA DOSTELData Analysis

23. MATROSHKA DOSTELData Analysis

24. MATROSHKA DOSTELData Analysis Average Dose Rate: D = T-1 D(LET) dLET GCR component: D = 221 µGy/d (in Si) SAA component: D = 201 µGy/d (in Si)

25. MATROSHKA DOSTELData Analysis Conversion from silicon to tissue dose: Dtissue = 1.21 * DSi GCR component: D = 267 µGy/d (in tissue) SAA component: D = 243 µGy/d (in tissue)

26. Mean Quality Factor

27. Mean Quality Factor Total Dose: D = D(LET) dLET Total Dose Equivalent: H = D(LET) Q(LET) dLET H Q = Mean Quality Factor: D

28. Mean Quality Factor GCR component: Q = 3.1 ± 0.3 SAA component: Q = 1.8 ± 0.3

29. Dose Equivalent Dose Equivalent: H = Q * D GCR component: H = 828 µSv/d SAA component: H = 437 µSv/d

30. Dose Equivalent GCR component: H = 828 µSv/d SAA component: H = 437 µSv/d Average Dose Equivalent: H = 1265 µSv/d

31. Comparison DOSMAP  MATROSHKA GCR component: GCR component: H = 828 µSv/d H = 385 µSv/d SAA component: SAA component: H = 437 µSv/d H = 138 µSv/d Average Dose Equivalent: Average Dose Equivalent: H = 1265 µSv/d H = 523 µSv/d

32. Ongoing and Future Activities EuTEF DOSTEL outside COLUMBUS MATROSHKA outside MATROSHKA inside Two perpendicular DOSTEL Units inside the European COLUMBUS module by the End of this year

33. Acknowledgements • Special Thanks to the ICCHIBAN Workinggroup and the HIMAC facility • Many Thanks to ESA/ESTEC for their support • The DOSTEL was supported by DLR (german aerospace center) under grants 50WB9906 and 50WB0526 • Thank you very much for your attention!