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InterSpec

spectral radiation analysis software

InterSpec v1.0.14 Release Notes (June 2026)

SAND2026-21613O

Release date: June 2026

Previous release: v1.0.13 (March 7, 2025)

InterSpec v1.0.14 is a significant update spanning approximately 730 commits to InterSpec, 90 commits to SpecUtils, and 4 commits to SandiaDecay. Highlights include a new Simple Activity Calculator, a graphical batch analysis tool for processing multiple spectrum files, major enhancements to the “Isotopics by nuclides” tool (including multiple relative efficiency curves, fluorescent x-rays, reactions, new constraint types, and improved calculations), a new Reference Spectra widget, Voigt peak shape support, improvements to peak fitting, dynamically displayed reference lines, as well as translations into many additional languages.

Nearly all new features, and many fixes are thanks to user requests, feedback, or contributions.

Please email InterSpec@sandia.gov with any bug reports, issues, or other support.


New Features

Batch Analysis GUI

Example use of graphical batch analysis tool to fit a source's activity in multiple files.
Example use of graphical batch analysis tool to fit a source's activity in multiple files.

A new graphical batch analysis tool has been added. When multiple spectrum files are dragged onto the application, a batch analysis dialog is presented, allowing users to process all of the files at once from within the application, without needing to use the command line.

Isotopics by Nuclides Enhancements

Example of using the Isotopics by Nuclides tool.
Example of using the Isotopics by Nuclides to determine the plutonium enrichment from a CZT spectrum.

The “Isotopics by nuclides” tool has received major improvements:

Reference Spectra Widget

Reference spectrum widget.
The reference spectra widget - includes over 200 of common field nuclides for a variety of mobile detection systems.

A new tool for loading and comparing reference spectra has been added. This allows users to browse directories of reference spectra and display them as interactive thumbnail charts alongside the main spectrum for easy comparison, and then load into the main part of the application for further analysis or comparison. For a variety of mobile detectors, the tool includes over 200 high-fidelity simulation spectra that represent source that are likely to be found in the field.

Simple Activity Calculator

Simple activity calculator screenshot.
Example use of the Simple Activity Calculator by just right clicking on a peak, selecting the tool, and then entering the distance.

A new “Simple Activity Calculator” tool has been added for quick, straightforward activity estimations from a single peak. Features include:

To use just right-click on a peak, and select “Quick <nuclide> Activity…”.

Fit Peaks for Source

Fit peaks for source example
Example use of the Fit Peaks for Source tool to fit La140 peaks in a spectrum.

A beta version of a “Fit Source” capability has been added, accessible from the Reference Photopeaks tab. This tool automatically fits peaks in the spectrum for a given nuclide/source, using the expected gamma lines and relative efficiencies to guide the fitting. Features include:

Peak Fitting Improvements

Kinematic Reference Lines

Dynamic ref line preview
Dynamic reference line tool being used to quickly identify peaks sources.

Added support for displaying kinematic reference lines for nuclear reactions on the spectrum chart - the reference lines intelligently update based on the mouse location. When multiple candidates exist at an energy, the display cycles through them automatically (every 2 seconds) or via arrow keys. A single left-click stops the cycling or advances to the next candidate. If you fit a peak while the dynamic reference line is showing, the peak will automatically be associated with that source. See the “FAQs” tab in the Welcome dialog for how to customize sources that can be shown, or probability of showing for a specific source.

Spectrum Files Tab Improvements

Spectrum Files tab
Dynamic reference line tool being used to quickly identify peaks sources.

Activity/Shielding Fit Improvements

Spectrum Files tab Spectrum Files tab
Pi diagram and 3D view of source/shielding setup. The detector can be hidden from these diagrams, and they are also interactive, giving more information on mouse over.

Isotopics from Peaks Improvements

Other New Features

Internationalization

If you have suggestions for your preferred language, please send them to InterSpec@sandia.gov - they would be greatly appreciated.

Spectrum File Format Improvements (SpecUtils)

Nuclear Data (SandiaDecay)


Bug Fixes

InterSpec

Many other small issues fixed or improved.

SpecUtils


Developer / Deployment Changes

InterSpec v1.0.13 Release Notes (March 2025)

SAND2026-21613O

Release date: March 5, 2025

Previous release: v1.0.12 (May 5, 2024)

InterSpec v1.0.13 is a major update spanning approximately 380 commits to InterSpec, 137 commits to SpecUtils, and 13 commits to SandiaDecay. Highlights include comprehensive internationalization of the application (with French translations), a new Simple MDA detection limit tool, significant improvements to mobile/portrait mode, expanded batch analysis capabilities with report templating, and numerous improvements to the database state management system.


New Features

Internationalization

Simple MDA (Minimum Detectable Activity) Tool

Preview of the Quick MDA tool
The Quick MDA tool is started by right-clicking on a spectrum; if reference photopeak lines are being displayed, the nuclide and energy gamma will already be filled out.

A simplified single-peak MDA tool has been added, and can be accessed by right-clicking on the spectrum, outside of any ROIs. If you are showing reference photopeak lines, the nuclide and energy will be filled out in the tool. Users can adjust the ROI used by the text fields, or the standard dragging of roi edges on the displayed chart. Users can also adjust the confidence level, number of side channels, or if it should use the standard Currie, or more advanced Deconvolution methods. The peak that would be expected at the computed limit is displayed for reference, and there is a “further details…” link that provides additional information about the ROI and calculation, along with descriptions.

Database and State Management Overhaul

Batch Analysis Improvements

Mobile and Portrait Mode

CI/CD

Spectrum Chart Improvements

Activity/Shielding Fit Improvements

Relative Activity Tools

Decay Chart

Other New Features

SpecUtils

SandiaDecay


Bug Fixes

InterSpec

SpecUtils

InterSpec v1.0.12 release notes (May 2024)

SAND2024-05524O

InterSpec v1.0.12 adds a number of new features and improvements, as well as fixes many bugs.
The largest new features are undo/redo support, new peak skew models, and a flexible spectrum file export tool.

Most features added were user requested, and a large amount of the bugs fixed were user reported - so please keep reporting issues and requesting improvements or information to InterSpec@sandia.gov.

New features and capabilities

Bug fixes

Expected features in v1.0.13

The next release of InterSpec is expected to focus on improving peak fits, adding support for languages other than English, and adding an advanced minimum detectable activity and maximum detectable distance calculator.

v1.0.11 (June 01, 2023)

SAND2023-05961O

InterSpec version 1.0.11 adds a number of new features and capabilities, many improvements, and a good amount of bug fixes.

Most of the added features were user requested, as were many of the improvements and bug fixes - thank you for these!

Questions, bug reports, suggestions, and feature requests are very welcome at InterSpec@sandia.gov.

New Features

Example of Isotopics by peaks tool
Time chart of the full energy range summed.
Textual results
The 170 keV to 190 keV range ratioed with 220 keV and above.

Bug Fixes

Known Issues for v1.0.11

Issues reported on v1.0.11:

v1.0.10 (Aug 07, 2022)

InterSpec version 1.0.10 fixes a number of smaller issues, improves some interfaces, makes using pre-defined detector response functions (DRFs) easier, adds a number of default DRFs for common portable detection systems, reduced app memory usage, and upgraded some underlying libraries.

Detailed changes for v1.0.10


v1.0.9 (Feb 06, 2021)

InterSpec version 1.0.9 adds a number of user requested features and user reported fixes. In particular, support for volumetric trace sources and cylindrical and rectangular geometries; these are particularly useful for determining contamination levels, or activities of bulk materials.

Detailed changes for v1.0.9

Time chart with settings icon
First click on the settings icon on the time chart.
In the data shown here you can see the gamma (black line) and neutron (green line) data obscure each other which could make it hard to see features of the data in either of the lines.
Filter tab
Select the "Filter" tab.
Here you can see other settings that can be useful for improving the view of the time data.
Emphasizing the gamma data.
Adjust the "Rel. y-max" value to be between 0.04 and 25. Values larger than 1.0 will cause the neutron y-axis range to be that multiple of neutron data range, while not effecting the gamma y-axis range. The value of "10.0" shown here causes the neutron y-axis to have a range ten times larger than the data, which emphasizes the gamma data.
Emphasizing the neutron data.
Values less than 1.0 cause the gamma y-axis range to be scaled by the inverse of the entered value, while not effecting the neutron y-axis range. The value of "0.5" shown here causes the gamma y-axis to have twice the range the data calls for, which causes the neutron data to be emphasized.
Popup window when loading CSV/TSV file
Example dialog after dropping a CSV/TSV DRF file onto InterSpec. If selected to

v1.0.8 (Sep 26, 2021)

InterSpec version 1.0.8 concentrates on improving application usability and bug fixes.

Thank you to all the users who reported bugs or requested features!

Detailed changes for v1.0.8

Example of using the new time chart controls
Example of using the time-chart settings widget to navigate the time-series chart, select samples to sum, and set energy range to display the time-chart for.
Example of displaying the time-chart for only a specified energy range.
Example of displaying the time-chart for only the 1163 keV to 1183 keV (i.e., the lower Co-60 full energy peak range) region.
Right-clicking on a peak and using the "Change Continuum" menu-item to select the continuum type.
Using the "Peak Editor" to change the continuum type.
Constant
Linear
Quadratic
Flat Step
Linear Step
Bi-linear Step

v1.0.7 (Feb 19, 2021)

InterSpec version 1.0.7 includes a complete revamp of how energy calibration is handled, a number of new features, lots of bug fixes and smaller improvements.

Detailed changes for v1.0.87


v1.0.6 (November 4, 2019)

This release is mostly stability improvements, small UX improvements, and bug fixes. Download Windows, Linux, and macOS binaries from: https://github.com/sandialabs/InterSpec/releases/tag/v1.0.6

v1.0.5 (August 23, 2019)

This release is mostly small bug fixes, improvements, and the addition of the Flux Tool. Download Windows, Linux, and macOS binaries from: https://github.com/sandialabs/InterSpec/releases/tag/v1.0.5

v1.0.4 (July 21, 2019)

This release primarily improves the interactivity with the spectrum. Download Windows, Linux, and macOS binaries from: https://github.com/sandialabs/InterSpec/releases/tag/v1.0.4

Interactions with the spectra:

All these videos are also available within InterSpec by going to the HelpWelcome… menu item, and then selecting the Controls tab.