SPENVIS includes an updated version of SHIELDOSE-2
(SHIELDOSE-2Q) which extends the shielding database behind the model to treat
higher energy electrons and different shield and target materials.
As with the previous version, SHIELDOSE-2Q is
relevant to trapped electrons and protons, and
solar proton fluence spectra.
The input parameters and options for the model are described below.
Input parameters
Shield depths
The required shielding thicknesses can be entered in three ways:
- using a set of default thicknesses
(in mm), ranging from 0.05 mm to 20 mm;
- as a table of values, in order of increasing thickness. A maximum of 50
values is allowed;
- a shielding distribution produced by
SSAT can be read in.
All thicknesses should be entered as Al equivalent values.
Shield configuration
The three options for shield configuration are: finite slab shields;
semi-infinite slab shields; centre of spherical shields (see figure below).
| Finite slab shielding |
Semi-infinite slab shielding |
Solid spherical shielding |
 |
 |
 |
| Source isotropically incident over 2π steradians |
Source isotropically incident over 2π steradians |
Source isotropically incident over 4π steradians |
Shield material
The options for the shield composition are:
- Aluminium
- Titanium
- Iron
- Tantalum
- CW80 copper tungsten alloy
- 1mm Al + Ta bi-layer
Target material
Target material options are:
- Al
- C, Graphite
- Si
- Air
- Bone
- CaF2
- GaAs
- LiF
- SiO2
- Tissue
- Water
- Polyimide
- Epoxy
- HfO2
- SiC
- InGaAs
- HgCdTe
- NaI
- MgO
- Ge
- Ti
- Fe
- Ta
- W
- CW80 Alloy
Note that the final two options for calculating the TNID in silicon and
GaAs are highly experimental, and subject to further analysis and
validation.
Results
SHIELDOSE-2Q produces the
files listed in the table below. A description of the format of the
files can be brought up by clicking on their description in the table.
The report file spenvis_sqp.html contains the input parameters
and summary tables.
The output file spenvis_sqo.txt
contains the total mission doses for the different particle types.
Output files generated by SHIELDOSE-2Q
| File name |
Description |
spenvis_sqp.html |
Report file |
spenvis_sqo.txt |
Total mission doses
|
References
S. M. Seltzer, "SHIELDOSE: A computer code for space-shielding radiation
dose calculations," National Bureau of standards Technical Note 1116, 1980.
S. M. Seltzer, Electron, electron-bremsstrahlung and proton dose-depth
data for space-shielding applications, IEEE Trans. Nucl. Sci., 26,
4896–4904, 1979.
S. M. Seltzer, Conversion of depth-dose distributions from slab to
spherical geometries for space-shielding applications, IEEE Trans.
Nucl. Sci., 33, 1292–1297, 1986.
S. M. Seltzer, "Technical progress report on predictions of dose from
electrons in space," NASA-CR-191617, 1982
S. M. Seltzer, "Updated calculations for routine space-shielding
radiation dose estimates: SHIELDOSE2," National Institute of Standards
and Technology report NISTIR 5477, December 1994.
P. Truscott, "JORE2M2 Project: SHIELDOSE-2Q Requirements, Interface
Control, Design, Implementation and Justification Document,"
QINETIQ/TS/AS/SDD0900017, 2010.
P. Truscott, "JORE2M2 Project: SHIELDOSE-2Q Software User Manual,"
QINETIQ/TS/AS/SUM1003576, 2010.
Last update: Mon, 12 Mar 2018