Bose–Einstein condensation of pions in high multiplicity events

We present microcanonical ensemble calculations of particle number fluctuations in the ideal pion gas approaching Bose–Einstein condensation. At high collision energy, in the samples of events with a fixed number of all pions, NπNπ, one may observe a prominent signal. When NπNπ increases the scaled variances for particle number fluctuations of both neutral and charged pions increase dramatically in the vicinity of the Bose–Einstein condensation line. As an example, the estimates are presented for p+pp+p collisions at the beam energy of 70 GeV.