Description
Return an exponential survival term from fluence and cross section.
Spectral and radiation quantities depend on their denominator coordinates, reference levels and physical definitions. A density per wavelength changes by a Jacobian when expressed per frequency, and photon counts, radiant energy, exposure and absorbed dose remain different quantities.
Return an exponential survival term from fluence and cross section.
When to use this tool
Use Neutron Fluence Cross Section Exponent Factor when checking the stated spectral, photon, attenuation or radiometric conversion.
How to use the tool and how it works
- Enter fluence, crossSection. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read opticalDepth, unreactedFraction. Use the output convention below.
Return an exponential survival term from fluence and cross section. Require both nonnegative; opticalDepth = fluence*crossSection, unreactedFraction = exp(-opticalDepth).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| fluence | Fluence | Required. Finite number; minimum 0. |
| crossSection | Cross Section | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| opticalDepth | Optical Depth | Required. Finite number. |
| unreactedFraction | Unreacted Fraction | Required. Finite number. |
{
"input": {
"fluence": 100000000000000000000,
"crossSection": 1e-20
},
"output": {
"opticalDepth": 1,
"unreactedFraction": 0.36787944117144233
}
}Limitations and assumptions
- Fluence and area units must cancel; this assumes the stated independent constant-cross-section model, without shielding, spectrum or dose assessment.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use a complete spectrum, measurement calibration and appropriate physical interaction model for integration, uncertainty or exposure interpretation.
References
Similar or alternative tools
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