PROFFIT: An interactive software for the analysis of 
X-ray surface-brightness profiles

PROFFIT is a stand-alone software for the analysis of galaxy cluster X-ray surface-brightness profiles, that can be used to analyze the data from any X-ray instrument. It has been used for the preparation of more than 20 scientific papers so far.

The software is released under the GNU Public License v2.0, so you are free to use it and redistribute it. If you find this software useful, please cite Eckert et al. 2011, A&A 526, 79. 

NEWS: Version 1.5 released (June 4, 2018). See the change log

The software is based on the ROOT data analysis framework ( and uses the CFITSIO library for accessing FITS files.

For documentation on the code, see the PROFFIT user guide (PDF version).

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PROFFIT runs on Linux, Mac OSX, and Solaris. To install PROFFIT, you will need to install ROOT v5.24 or newer (see the download page) and the CFITSIO and WCS libraries. Binary distributions are sufficient. To use the MultiNest version, you will also need to install the MultiNest package (see here).


Multinest version: proffit_1.5_multinest.tar.gz
Cmake version: proffit_1.5_cmake.tar.gz
Autoconf version: proffit_1.5_autoconf.tar.gz

Cmake version: proffit_1.4_cmake.tar.gz
Autoconf version: proffit_1.4_autoconf.tar.gz

Autoconf version: proffit_1.3.tar.gz

Autoconf version: proffit_1.2.tar.gzProffit_files/changelog.txt
  1. Command-line interface similar to HEASOFT’s XSPEC package

  1. Extraction of surface-brightness profiles in circular or elliptical annuli, using constant or logarithmic bin size, from the image centroid, the surface-brightness peak, or any user-given center

  1. Surface-brightness profiles in any circular or elliptical sectors

  1. Excision of areas using SAODS9-compatible region files to exclude point sources

  1. Background map support to extract background profiles

  1. Fitting with a number of built-in models, including the popular beta model, double beta, cusp beta, power law, and projected broken power law

  1. Fitting using chi-squared or C statistic

  2. Fitting on the surface-brightness or counts data

  3. Possibility to include a flat level of systematic uncertainty

  1. Possibility to define the radial range for fitting and to fix or let free the parameters

  1. 1, 2, and 3 sigma contour plots for a given set of parameters

  1. Accurate error calculation on the parameters at any confidence level

  1. Easy grouping of the bins to ensure a minimum number of counts or S/N per bin

  1. Interactive plotting interface inherited from ROOT

  1. Geometrical deprojection using the Kriss et al. method, allowing to easily derive deprojected density profiles

  1. Option to compute the azimuthal scatter of the profile split into different sectors

  1. Convolution of the profile with the instrumental PSF, using Gaussian or King profile

  1. Extraction of growth curves

  1. Option to save the results in FITS, ROOT or TXT format

  1. Possibility to save the deviations of the image from the best-fit surface-brightness profile to create a substructure image

  1. Interactive help with a description of all the commands

XMM/MOS2 surface-brightness profile of A2204 fitted with a double beta model, see Eckert et al. 2011, A&A 526, 79

1, 2, and 3 sigma contour plot for the best-fit parameters of A2204

ROSAT/PSPC deprojected profile of PKS 0745-191 (from Eckert et al. 2011, arXiv:1103.2455)

Substructure image of A545 after subtraction of the best-fit beta model, showing a possible shock front. From Barrena et al. 2011, arXiv:1103.0679