Measurement of collective flow in heavy-ion collisions using particle-pair correlations

We present a new type of flow analysis, based on a particle-pair correlation function, in which there is no need for an event-by-event determination of the reaction plane. Consequently, the need to correct for dispersion in an estimated reaction plane does not arise. Our method also offers the option to avoid any influence from particle misidentification. Using this method, streamer chamber data for collisions of Ar+KCl and Ar+${\mathrm{BaI}}_2$ at 1.2 GeV/nucleon are compared with predictions of a nuclear transport model.