VisRes: A GRACE tool for displaying and analysing resonances Original Research Article

VisRes is a graphical tool for displaying and analysing resonance data. Files of eigenphase sums, generated during the computation of electron and photon interactions with atoms and molecules, can be read and the data displayed both as continuous and discontinuous graphs. Resonance resolution can be improved by interactively computing additional data points and merging them with the displayed data. Resonance positions and widths are determined by fitting user selected data points by the Breit—Wigner formula. VisRes is written in C and Motif for the UNIX operating system. It can be operated exclusively on the host workstation or in distributed mode where data is read from and computed on a remote computer but displayed and analysed on the host workstation. While it is published as a stand-alone tool, VisRes also forms part of the Graphical R-matrix Atomic Collision Environment (GRACE).