palsfit.dk

What It Is

PALSfit3 is a desktop computer program dedicated to the analysis of positron annihilation lifetime spectroscopy (PALS). Developed by the Technical University of Denmark, it is the latest iteration of the classic PATFIT and PALSfit programs. It primarily serves researchers in the field of positron annihilation, helping them process and fit experimentally measured spectral data.

Core Features

The tool is built around two fitting modules: PositronFit and ResolutionFit. PositronFit extracts the mean lifetime, broadening, and intensity of each lifetime component from measured spectra, and supports “source correction” for annihilation outside the sample. ResolutionFit is used to fit and determine the parameters of the time-resolution function; the extracted resolution function can then be used directly in PositronFit. The model function consists of a physical function (a sum of decaying exponentials, which can be broadened by a log-normal distribution) convolved with the experimental time-resolution function (a sum of Gaussians), plus a constant background. The software also provides improved graphical output, making it easier to choose input parameters and present analysis results. It is currently compatible with Windows 7 through 11.

Pricing and Access

Since November 15, 2022, PALSfit3 licenses have been completely free and include access to all future updates. However, obtaining the full version still involves a rather old-fashioned process: users must print and sign the standard license agreement, scan it, and email it to the Technical University of Denmark to request a license key. Users who prefer not to go through this process can download the demo version, but it is functionally limited—for example, only PositronFit is available, and the number of channels and lifetimes is restricted.

Pros and Cons

Pros: 1. Strong academic pedigree, built on widely used classic software, giving its results a high degree of authority; 2. Completely free, with a commitment to ongoing updates; 3. Provides a graphical interface to assist with parameter selection and result presentation, lowering the barrier to use; 4. Comes with test data and detailed official reports/literature support.
Cons: 1. The licensing process is overly traditional, requiring physical printing and scanning, which is inconvenient; 2. Windows-only, with no cross-platform support; 3. As an extremely specialized research tool, it has a very narrow audience and lacks the APIs or ecosystem integrations common in modern developer tools.

Who It’s For

PALSfit3 is strictly aimed at researchers and students conducting positron annihilation spectroscopy experiments in fields such as materials science and condensed matter physics. For laboratories that need accurate fitting of lifetime spectra and resolution functions, it is an indispensable analysis tool.

Access from China

As a site hosted under a Danish academic domain, the PALSfit3 official website is directly accessible from China. Users can download the program and demo version and consult the documentation smoothly, without needing a proxy.