Vaandrager, PaulRakityansky, Sergei Anatoljevich2016-08-052016-02Vaandrager, P & Rakityansky, SA 2016, 'Extracting the resonance parameters from experimental data on scattering of charged particles', International Journal of Modern Physics E, vol. 25, no. 2, art #1650014.0218-3013 (print)1793-6608 (online)10.1142/S0218301316500142http://hdl.handle.net/2263/56211A new parametrization of the multi-channel S S -matrix is used to fit scattering data and then to locate the resonances as its poles. The S S -matrix is written in terms of the corresponding “in” and “out” Jost matrices which are expanded in the Taylor series of the collision energy E E around an appropriately chosen energy E 0 E0 . In order to do this, the Jost matrices are written in a semi-analytic form where all the factors (involving the channel momenta and Sommerfeld parameters) responsible for their “bad behavior” (i.e., responsible for the multi-valuedness of the Jost matrices and for branching of the Riemann surface of the energy) are given explicitly. The remaining unknown factors in the Jost matrices are analytic and single-valued functions of the variable E E and are defined on a simple energy plane. The expansion is done for these analytic functions and the expansion coefficients are used as the fitting parameters. The method is tested on a two-channel model, using a set of artificially generated data points with typical error bars and a typical random noise in the positions of the points.en© 2016 World Scientific Publishing Co. Electronic version of an article published as International Journal of Modern Physics E, vol. 25, no. 2, art. #1650014, 2016. doi : 10.1142/S0218301316500142. The original publication is available at : http://www.worldscientific.com/worldscinet/ijmpe.Jost matrixMulti-channel resonancesResonancesEnergy Riemann surfaceCoulomb forcesPostprint Article