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arXiv · 2506.18216

TasVisAn and InsPy -- Python Packages for Triple-Axis Spectrometer Data Visualization, Analysis, Instrument Resolution Calculation, and Convolution

Abstract

Experimental data collected from a triple-axis spectrometer (TAS) are typically analysed by considering the instrument resolution, as the resolution of a TAS instrument is often complex and significantly influences the measured results. Two Python packages, TasVisAn and InsPy, have been developed to visualize and analyse data from TAS instruments - particularly from the cold-neutron TAS Sika and the thermal-neutron TAS Taipan at the Australian Centre for Neutron Scattering. TasVisAn offers a range of functions, including data importing, reduction, plotting, contour mapping, convolution fitting, and more, for data collected on TAS instruments, especially on Sika and Taipan. It also supports data reduction of the current trendy multi-analyser and multiplexing TAS instruments, including the multiplexing mode of Sika. Besides, it includes scan simulation and batch file validation tools for both Taipan and Sika, assisting users in designing and planning experiments in advance. InsPy is a general-purpose Python package designed to calculate the four-dimensional (4D) instrument resolution in momentum-energy space for any TAS instrument. Combined with InsPy, TasVisAn supports both instrument resolution calculation and resolution-convoluted data fitting. Its flexible external data import feature further allows TasVisAn to be adapted for the visualization and convolution analysis of inelastic neutron scattering data across various TAS instruments.

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BibTeXRIS

Guochu Deng, Garry J. McIntyre. 2025-06-23. TasVisAn and InsPy -- Python Packages for Triple-Axis Spectrometer Data Visualization, Analysis, Instrument Resolution Calculation, and Convolution. https://doi.org/10.1107/s1600576725008180

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