  PURPOSE: To update the Carleton Laboratory for Radiotherapy Physics (CLRP)
TG-43 dosimetry database for low-energy (< 50 keV) photon-emitting low-dose
rate (LDR) brachytherapy sources utilizing the open-source EGSnrc application
egs_brachy rather than the BrachyDose application used previously for 27 LDR
sources in the 2008 CLRP version (CLRPv1). CLRPv2 covers 40 sources (Pd-103,
I-125, Cs-131). A comprehensive set of TG-43 parameters is calculated,
including dose-rate constants, radial dose functions with functional fitting
parameters, 1D and 2D anisotropy functions, along-away dose-rate tables,
Primary-Scatter separation dose tables (for some sources), and mean photon
energies. The database also documents the source models which will become part
of the egs_brachy distribution. METHODS: Datasets are calculated after a
systematic recoding of the source geometries using the egs++ geometry package
and its egs_brachy extensions. Full scatter water phantoms with varying voxel
resolutions in cylindrical coordinates are used for dose calculations. New
statistical uncertainties of source volume corrections for phantom voxels which
overlap with brachytherapy sources are implemented in egs_brachy, and all
CLRPv2 data include these uncertainties. For validation, data are compared to
CLRPv1 and other data in the literature. DATA ACCESS/FORMAT: Data are available
at https://physics.carleton.ca/ clrp/egs_brachy/seed_database_v2. As well as
being presented graphically in comparisons to previous calculations, data are
available in Excel (.xlsx) spreadsheets for each source. APPLICATIONS: The
database has applications in research, dosimetry, and brachytherapy planning.
This comprehensive update provides the medical physics community with more
accurate TG-43 dose evaluation parameters, as well as fully-benchmarked source
models distributed with egs_brachy.
