linear energy transfer

Identify defining convention

Record the defining authority, edition and expression; unrestricted LET is numerically associated with collision stopping power. [NIST stopping-power report](https://nvlpubs.nist.gov/nistpubs/Legacy/IR/nbsir82-2550A.pdf)

1. Which reference and mathematical definition establish the meaning of LET in this record? definition
2. Does the supplied quantity include radiative or nuclear losses that place it outside that LET definition? boundary

Resolve cutoff semantics

Record Δ and the exact rule for excluding energy associated with secondary electrons; verify equivalence before substituting a restricted stopping-power implementation. [ICRU Report 35](https://www.nist.gov/system/files/documents/calibrations/icru-35.pdf)

1. What is Δ, and is the quantity restricted or explicitly unrestricted? measurement
2. Does the implementation restrict secondary-electron kinetic energy, total energy transfer or another specified contribution? definition

Bind LET to particle state

Require the particle identity, local kinetic energy and any charge-state assumptions used in calculation.

1. Which charged-particle species and local energy or energy spectrum does the LET describe? measurement
2. For a photon or neutron field, which secondary charged particles supply the tracks represented by this LET? boundary

Establish medium basis

Record composition, density and any conversion to a reference material such as water.

1. Is the value LET in the traversed material or a calculated LET in a reference material? definition
2. Is the reported quantity L or L/ρ, and which density and units support conversion? measurement

Define spectrum support

Specify species inclusion, LET bins, spatial extent and normalization before interpreting a spectrum.

1. Are primary particles, secondary electrons, recoil ions and nuclear fragments included or excluded? boundary
2. What location, voxel size, LET binning and normalization define the distribution? measurement

Preserve weighting rule

Record track or dose weights, denominators and aggregation order; segment-based approaches also require explicit track-segment assumptions. [Segment-averaged LET research](https://aapm.onlinelibrary.wiley.com/doi/abs/10.1002/mp.13673)

1. What exact numerator, denominator and weights define the reported average? definition
2. Can regional LET be recomputed from underlying weighted contributions rather than an unweighted average of voxel averages? action

Trace LET estimator

Record the table or transport implementation, or the detector-response inversion, together with its material and energy applicability.

1. Which dataset, software version, physics settings or detector calibration generated the estimate? provenance
2. If derived from deposited energy or lineal energy, what reconstruction makes the output an estimate of the declared LET? measurement

Qualify estimate stability

Track sensitivity to transport thresholds, step lengths, scoring resolution, material inputs and sampling, distinguishing numerical settings from the physical LET cutoff.

1. How does the estimate change when step limits, production thresholds, voxel size or sample count are varied? measurement
2. Which independent benchmark supports the stated uncertainty for this particle, medium and energy range? provenance

Establish comparable LET

Require compatible restriction, medium, particle inclusion, weighting and spatial support, or an explicit justified transformation.

1. Which defining conditions differ between these LET results, and can those differences be reconciled? boundary
2. What application-specific threshold and reference population justify calling this LET high or low? definition

Bound effect inference

Record the endpoint and response model before using an average LET to infer biological effectiveness; the adequacy of dose-averaged LET depends on response assumptions. [RBE prediction study](https://aapm.onlinelibrary.wiley.com/doi/abs/10.1002/mp.13347)

1. Which endpoint, particle types, dose conditions and biological system support this LET-to-effect relationship? boundary
2. Does the intended decision require a LET spectrum, track-structure information or other evidence beyond the reported average? action

Check these first

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these check these first hold for the sense of linear energy transfer this model covers, and on what evidence? provenance

Kinds and varieties

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these kinds and varieties hold for the sense of linear energy transfer this model covers, and on what evidence? provenance

Standards and regulation

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these standards and regulation hold for the sense of linear energy transfer this model covers, and on what evidence? provenance

Real-world use

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these real-world use hold for the sense of linear energy transfer this model covers, and on what evidence? provenance

Typical measurements

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these typical measurements hold for the sense of linear energy transfer this model covers, and on what evidence? provenance

Failure modes and hazards

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these failure modes and hazards hold for the sense of linear energy transfer this model covers, and on what evidence? provenance

Neighbouring kinds and how to tell them apart

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these neighbouring kinds and how to tell them apart hold for the sense of linear energy transfer this model covers, and on what evidence? provenance