MétaCan
Menu
Back to cohort
Record W2027859447 · doi:10.1118/1.2962781

WE‐E‐AUD B‐07: EGSnrc Benchmarking Against High‐Precision Angular Electron Scattering Data Through Thin Foils

2008· article· en· W2027859447 on OpenAlexaboutno aff
C Cojocaru, C. K. Ross, M R McEwen, A McDonald, Bruce Faddegon

Bibliographic record

VenueMedical Physics · 2008
Typearticle
Languageen
FieldMaterials Science
TopicElectron and X-Ray Spectroscopy Techniques
Canadian institutionsnot available
Fundersnot available
KeywordsPhysicsMonte Carlo methodElectronScatteringCathode rayBeam (structure)Computational physicsDosimetryElectron scatteringGaussianAbsorbed doseAtomic physicsOpticsIrradiationNuclear physicsNuclear medicineStatisticsMathematics

Abstract

fetched live from OpenAlex

Purpose: The EGSnrc Monte Carlo code was benchmarked against newly measured angular scattering distributions of electron beams through thin materials. Method and Materials: The BEAMnrc user code was used for the simulation of the experimental setup. The geometry, beam and material properties were implemented in BEAMnrc, while the DOSXYZnrc user code was used to score the absorbed dose up to angles of 10°. The electron beam was generated using the National Research Council of Canada (NRC) Vickers linear accelerator, which allows for the production of narrow pencil beams of electrons with well known energies. Six materials: Be, C, Al, Ti, Cu, Ta and Au, were used as scattering foils and measurements were made at two energies — 13 MeV and 20 MeV. Great care was taken to obtain high accuracy experimental data for comparison with the results of the simulations. Results: The obtained angular distributions were fitted with a Gaussian and the characteristic angle (the angle at which the absorbed dose decreases by 1/e) was used to compare the measured and simulated distributions. The discrepancy between the measured and the EGSnrc characteristic angles is on average about 1.5%. A careful error estimation was performed on the measured data, that resulted in a value of about 1%. The EGSnrc code shows an agreement with the measured data at the 2σ level. In general, the EGSnrc predicts narrower distributions. The full distributions were also compared and the shapes were found to be very similar even at large angles. Conclusion: The present study shows that the EGSnrc code predicts electron angular scattering distributions in agreement with the measured data at the 2% level. It is intended to make the experimental data available to the user community to be used for benchmarking of other Monte Carlo codes. Partial support from NIH R01 CA104777‐01A2.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.006
metaresearch head score (Gemma)0.007
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Bench or experimental · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.012
Threshold uncertainty score0.034

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0060.007
Meta-epidemiology (narrow)0.0010.000
Meta-epidemiology (broad)0.0010.001
Bibliometrics0.0020.002
Science and technology studies0.0010.001
Scholarly communication0.0020.001
Open science0.0020.001
Research integrity0.0020.001
Insufficient payload (model declined to judge)0.0040.002

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.030
GPT teacher head0.307
Teacher spread0.278 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designBench or experimental
Domainnot available
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations0
Published2008
Admission routes1
Has abstractyes

Explore more

Same venueMedical PhysicsSame topicElectron and X-Ray Spectroscopy TechniquesFrench-language works237,207