Speaker
Description
The investigation of preliminary results for mean negatively charged pion multiplicities $\langle \pi^- \rangle$ from Ar+Sc collisions is the main topic of the talk.
The data has been taken recently by the NA61/SHINE collaboration for a wide range of momenta - 13, 19, 30, 40, 75 and 150 A GeV/c. Starting with rapidity distibution of differential spectra
$\frac{dn}{dy}$ extrapolated to unmeasured regions, the procedure of obtaining the final multiplicities is presented. The mean number of wounded nucleons
$\langle W\rangle$ extracted from Glissando MC model is used to obtain the $\langle \pi^- \rangle/\langle W\rangle$ ratio. Using data from other experiments,
the comparison of $\langle \pi^- \rangle/\langle W\rangle$ for different collisions and momenta is discussed.
