A curve fitting program for small-angle scattering curves, mostly from SAXS and SANS experiments in analytical or biological chemistry. For a basic overview and reference, please see: I. Breßler, J. Kohlbrecher, A. F. Thünemann, "SASfit: a tool for small-angle scattering data analysis ...". J. Appl. Cryst. 48: 1587-1598, http://dx.doi.org/10.110…
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Software package SASfit for fitting small-angle scattering curves

SASfit has been written for analyzing and plotting small angle scattering data. 
It can calculate integral structural parameters like radius of gyration, scattering invariant, 
Porod constant. Furthermore it can fit size distributions together with several form factors 
including different structure factors. Additionally an algorithm has been implemented, which allows
to simultaneously fit several scattering curves with a common set of (global) parameters. This last
option is especially important in contrast variation experiments or measurements with polarised 
neutrons. The global fit helps to determine fit parameters unambiguously which by analysing a single
curve would be otherwise strongly correlated. The program has been written to fulfill the needs at 
the small angle neutron scattering facility at PSI (kur.web.psi.ch). The numerical routines have 
been written in C whereas the menu interface has been written in tcl/tk and the plotting routine 
with the extension blt.

Author Information:
Joachim Kohlbrecher (joachim.kohlbrecher@psi.ch)
Ingo Bressler (ingo.bressler@bam.de)

Laboratory for Neutron Scattering
Paul Scherrer Institut
CH-5232 Villigen PSI
Tel: +41 (0)56 310 3165
Fax.: +41 (0)56 310 3131

SASfit is available for users analysing data taken at PSI
SASfit has been developed at the Paul Scherrer Institute (PSI) and remains copyright of the PSI.
SASfit is provided for users of the PSI facilities
SASfit is provided "as is" and with no warranty.

For license information see COPYING.txt.

A paper about SASfit has been published in
J. Appl. Cryst. (2015). 48, 1587-1598