Isotope Spectrum Builder

Generate detector-aware gamma-ray spectra by combining:

• Signal events from Geant4 simulations
• Background events from resampling a real measured background spectrum

Live demo: https://spectrum-builder.streamlit.app

Features

• Detector selection: NaI(Tl), CZT, HPGe (shown only if datasets exist)
• Isotope selection (auto-populated from datasets)
• Binning: 1024 / 2048 / 4096
• Optional custom energy range ([E_{min}, E_{max}]) in keV
• Sampling with replacement (supports more events than in the dataset)
• Normalization:
  • raw counts
  • counts per second (cps)
  • unit-area (Σ = 1)
• Exports:
  • CSV spectrum
  • PNG image with embedded attribution and isotope name

Installation (local)

python -m venv .venv
source .venv/bin/activate   # Windows: .venv\Scripts\activate
pip install -r requirements.txt
streamlit run app.py


## Installation from PyPI

Spectrum Builder can be installed directly from PyPI:

```bash
pip install spectrum-builder

Then run the web application with

spectrum-builder-app

The batch scripts can be accessed using
-spectrum-builder-batch
-spectrum-builder-sweep