line fitting tool designed for emission line spectra with low count numbers

Version : 3.2
Author(s) : Jan-Uwe Ness - ( , Rainer Wichmann - (
License : GPL
Website :

Installs from Open Source Astronomy for Mac OS X cd 1
Disk space required for installation is 15.72 Mb

After the package is installed it can be accessed using the command



A shortcut will be installed in the KDE/GNOME desktop menu system,
as an entry in the Astronomy submenu


The following printable documents will be installed :


The cora line fitting package consists of seven programs. Help on command line options can be obtained with the option -h.

cora_fit - this is the main fitting program. It can be used as a standalone command-line application, or it can be used from the graphical user interface. cora_fit requires a parameter file, and a spectrum. cora - this is the optional graphical user interface, which acts as a graphical front-end to cora_fit, and significantly facilitates the use of the latter. Basically, with cora you can: browse the spectrum and interactively choose lines to fit interactively set all parameters required by cora_fit, easily switch between different parameter settings, call cora_fit with the currently selected parameter settings obtain updated parameters and graphical output (i.e. plots). cora_inp - this is a helper application that writes a parameter file (see below) that is specifically adapted to a particular spectrum. This program is useful if you do not use the GUI. It is also used by the GUI itself. cora_spec - a small program to create an artificial spectrum with a few lines; for testing purposes. cora_rgs - converts a fits data file in the format returned by the XMM SAS task rgsproc into a CORA file cora_tex - converts the log file into a LATEX table cora_flux - creates a data file in the CORA format with fluxes using a given file with effective areas (two columns: wavelengths, area in cm) and exposure time. WARNING: Not recommended for obtaining line fluxes with CORA.

In addition, two scripts are provided with the package.

cora_setup.ksh and cora_setup.tcsh can be modified to your system and executed in order to set environment variables. This customizes the installation. will reduce XMM-RGS data using the SAS software. The user has to modify environment variables indicating where SAS is installed and where the data to be processed are located.