OWEN
Open Workflow for Engineered Neutronics
Text editor and 3D viewer for MCNP, OpenMC, Serpent, and SCONE files.
Multi-tab editor
Syntax highlighting, minimap, block selection, word wrap
3D and 2D preview
Rotate, zoom, pan, cross-sections
Lattice Builder
Visual grid editor for pin maps
Templates
Pin cells, assemblies, quarter-core, BWR bundles
v1.0.0 • Windows 10/11 • ~330 MB
Released March 2026 • A DynamicMC Product | ReactorMC
Security & Privacy
OWEN does not collect or transmit any data. No telemetry, analytics, or network calls. Your input files stay on your machine.
Downloads are hosted on GitHub Releases with signed tags. Verify integrity using the SHA-256 checksums published on each release page.
Air-gapped use: Download the installer on a connected machine, verify the checksum, then transfer via USB or approved media. OWEN runs fully offline after installation.
If your organization handles sensitive or export-controlled nuclear data, follow your internal policies for software approval.
View releases and checksums → Verify script (PowerShell) Security policy
Previous versions
Coming soon
OWEN is moving to VS Code
The next generation of OWEN will ship as a VS Code / Cursor extension — putting syntax highlighting, input validation, NRDP material lookup, workflow automation, and community model search inside the editor you already use.
Integrated workflows
Launch solvers, queue parametric sweeps, and collect results without leaving the editor. Define a parameter range, hit run, and let the extension handle the rest.
NRDP material access
Pull material cards straight from the Nuclear Reference Data Portal. Search by name or ZAID and insert ready-to-use definitions into your input file.
Input validation
Catch syntax errors, missing cross-section suffixes, and common modeling mistakes before you submit a run — a pre-flight checklist for your input deck.
Community models — now live on the web
Browse and download reactor input files shared by other engineers on ReactorMC — benchmarks, teaching models, and full-core designs ready to run. The OWEN extension will surface the same library inside the editor.
The standalone desktop editor above remains available for air-gapped and offline work.