Study of multiparticle azimuthal correlations in central CNE, MgMg, CCu, and OPb interactions at energy of 3.7 GeV per nucleon

Abstract

Azimuthal correlations between protons and between pions have been investigated in central CNe, MgMg, CCu and OPb collisions at energy of 3.7 GeV/nucleon. "Back-to-back" (negative) correlations have been observed for protons in CNe, CCu and for π − -mesons in CNe and MgMg collisions. For π − -mesons "side-by-side" (positive) azimuthal correlations have been observed for heavy systems of CCu and OPb. The Quark Gluon String Model satisfactorily describes the experimental results both for protons and π − -mesons. PACS numbers: 25.75.Ld

Study of azimuthal correlations in the target fragmentation region in p, d, He, C+C, Ta and C+Ne, Cu collisions at momenta of 4.2, 4.5 and 10 A GeV/c

“…The back-to back emission of protons can be understood as results of (local) transverse momentum conservation [16]. Back-to-back (ξ < 0, ζ < 1) pion correlation for light systems p, d, He, C + C and C + Ne, and the sideby-side pion azimuthal correlations ( ξ > 0 and ζ > 1) for heavy, asymmetric pairs -p, d, He, C + Ta and C + Cu, i. e. change of the pion's azimuthal correlation type, are in agreement with our previous results [20,21]. Also, the sideby-side correlations of pions have been observed in p+Au collisions at Bevalac (4.9 GeV/nucleon) and CERN-SPS (60 and 200 GeV/nucleon) energies [16].…”

“…Because, the azimuthal correlation function was defined in the target fragmentation region, the correlation parameters in the wide range of energy increases inappreciable. We applied this method also in our previous articles [20,21], where the analysis was carried out in the whole rapidity region instead of the target fragmentation region [15,16]. In the case, instead of y 0 -an average rapidity of participant protons for each colliding pears, y c was used.…”

“…We have investigated multiparticle azimuthal correlations of protons and pions in central and minimal bias inelastic collisions (4.2, 4.5 and 10 GeV/c/nucleon) within two experimental setups -2 m streamer chamber placed in a magnetic field (SKM-200-GIBS) and 2 m Propane Bubble Chamber (PBC-500) of JINR. In order to investigate the mechanism of nucleusnucleus interactions we have studied the correlations of these particles (protons, pions, Λ-hyperons) with respect to the reaction plane (directed and elliptic flows) [17]- [19], as well as with respect to the opening angle between particles emitted in the forward and backward hemispheres [20,21].…”

Multiparticle azimuthal correlations in central nucleus-nucleus collisions at high energy

“…The most impressive results of relativistic nucleus-nucleus collision experiments are new collective phenomena discovered in these studies. The studies of multiparticle azimuthal correlations are important for understanding the space-time evolution of the collective system [3].…”

“…where ȳ is the average rapidity of the particles produced in the event. Let ψ be the angle between the transverse momentum of a considered particle emitted in the backward (or forward) hemisphere and the vector Q B (or Q F ) and ϕ the angle between the vectors Q B and Q F [3]. Then, the multiparticle azimuthal correlation function is constructed as dN/dψ and dN/dϕ.…”