DOSTEL Dosimetry Measurements Aboard ISS

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DOSTEL Dosimetry Measurements Aboard ISS

• S. Burmeister1 , R. Beaujean1 , T. Berger2 , G.
  Reitz2
• 1 Universität Kiel/IEAP, 24098 Kiel, Germany
• 2 DLR Köln/Flugmedizin, 51147 Köln, Germany

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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.
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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

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DOSMAP DOSTEL
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DOSMAP DOSTEL
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DOSMAP DOSTEL Data
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Easter Event 2001
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Easter Event 2001
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Count Rate Mapping
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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

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DOSTEL Data Analysis
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DOSTEL Data Analysis
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DOSTEL Data Analysis
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DOSTEL Data Analysis
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MATROSHKA DOSTEL
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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
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MATROSHKA DOSTEL
Power- and signal-connection to Electronics Box
Canberra PIPS (behind Kapton cover)
Charge sensitive amplifiers
Hamamatsu PIN
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MATROSHKA DOSTEL
Block Diagram of DOSTEL Electronics
DOSTEL
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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.
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MATROSHKA DOSTELData Analysis
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MATROSHKA DOSTELData Analysis
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MATROSHKA DOSTELData Analysis
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MATROSHKA DOSTELData Analysis

D(LET) dLET
D T-1
Average Dose Rate
GCR component
D 221 µGy/d (in Si)
SAA component
D 201 µGy/d (in Si)
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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)
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Mean Quality Factor
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Mean Quality Factor
D(LET) dLET
D
Total Dose
D(LET) Q(LET) dLET
H
Total Dose Equivalent
H
Q
Mean Quality Factor
D
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Mean Quality Factor
GCR component
Q 3.1 0.3
SAA component
Q 1.8 0.3
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Dose Equivalent
Dose Equivalent
H Q D
GCR component
H 828 µSv/d
SAA component
H 437 µSv/d
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Dose Equivalent
GCR component
H 828 µSv/d
SAA component
H 437 µSv/d
Average Dose Equivalent
H 1265 µSv/d
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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
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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
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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!