History of XANADU
While in graduate school, Keith Arnaud came up with the name XANADU ("X-ray ANalysis And Data Use") to describe the various programs being written at the Institute of Astronomy to analyze data from EXOSAT, an X-ray astronomy satellite from the European Space Agency. These programs were written under the leadership of Andy Fabian by Tom McGlynn, Allyn Tennant, Rick Shafer, and Keith Arnaud. Among these programs were XSPEC, written by Rick Shafer, and QDP/PLT, written by Allyn Tennant.At the same time, the EXOSAT scientific team at ESA (Darmstadt and then ESTEC) were also writing data analysis software. Paulo Giommi led the development of the XIMAGE program for the analysis of X-ray astronomical imaging data and Luigi Stella with assistance from Lorella Angelini wrote the XRONOS tools for timing analysis.
When Nick White moved from leading the EXOSAT team to become the first director of the HEASARC, he brought XIMAGE and XRONOS with him. These were combined with XSPEC and QDP/PLT to provide the HEASARC's data analysis package under the name XANADU.
In parallel, a set of tools for manipulating FITS files were written, initially for the ASCA mission, and named Ftools. Later the Ftools and XANADU were combined in a single distribution, initially called lheasoft and then HEASoft.
In 2025, the XANADU term was dropped for simplicity.
The packages which made up XANADU and which are now distributed in HEASoft: