Stefan Schmitt, DESY Hamburg
Notkestr. 85, 22607 Hamburg, GERMANY

Phone: +49-40-8998-3560

Latest TUnfold release: Version 17.9, released on: November 20, 2019


The class TUnfold can be used to unfold measured data spectra and obtain the underlying "true" distribution. The input to the unfolding procedure is: There may also be histograms with background to the measured distribution and systematic uncertainties connected to the 2-dimensional histogram of migrations. These two cases are handled by the class TUnfoldSys, which provides methods to do systematic error propagation and to do unfolding with background subtraction. Together with complex binning schemes or multi-dimensional distributions all this is best handled by TUnfoldDensity and TUnfoldBinning.

It is strongly recommended to download and use the latest version of TUnfold from this web-page. The version distributed with the root package often is outdated and does not contain the latest bug fixes. First try the latest version, then report problems and new requests to .


TUnfold version history and download

TUnfold versions and root versions

Note: as of root version 5.22, TUnfold is included in the root package. However, the version implemented in root may not be up-to date. Check the version table below and use a local copy of TUnfold when necessary.

Relation of distributed Root version, TUnfold version and functionality:

Root VersionTUnfold versionTUnfoldSysTUnfoldDensity
5.23 to 5.2613yesnonono
5.28 to 5.3416.0yesnonono
6.00 to 6.0817.1yesyesnono
6.10 17.6yesyesyesno

TUnfold bugs

TUnfold improvements wish-list

Updates and plans for the future

Please contact in case you wish to contribute to the project or if you have requests to implement additional features.