Evidence of forward–backward correlation of pions in ultra-relativistic ring- and jet-like events in $$^{16}O-Ag/Br$$ interactions at $$E_{lab}=60$$ A GeV

Abstract

An investigation on the presence of the forwardbackward correlations in the pions multiplicity, emitted in 16 O − Ag/Br interactions at energy E lab = 60 A GeV are carried out. The study of the forward-backward correlation between various observables which is separated by two different pseudorapidity intervals can be treated as an important probe to defining the primordial conditions for the formation of the Quark Gluon Plasma (QGP). We have observed the dependency of correlation fluctuations and correlation strength on pseudorapidity (η) and the increasing width of the pseudorapidity bin size Δη. The roughness of the multiplicities and the particle number deviations are also investigated. The nuclear photographic emulsion technique has been employed to collect the experimental data. We have performed the FRITIOF and Ultra-relativistic Quantum Molecular Dynamics (UrQMD) simulations to compare the experimental results with the simulated results. The analysis strongly indicates the presence of forward-backward correlations in the experimental distributions of pions beyond statistical noise. We have also analyzed the ring-and jet-like structure to confirm the presence of the forward-backward correlations in the multiplicities of 16 O − Ag/Br interactions at 60 A GeV. We have also taken the variations of correlation fluctuations and correlation strength in η and Δη space, respectively for the ring-like and jet-like structure. The average behavior of correlation parameters of ring-like events strongly differs from jet-like events due to expected Cherenkov Gluon radiation.

Study of forward–backward correlation and multiplicity fluctuations of pions produced in p–p collisions at recent LHC energies

“…However, it is worthwhile to mention that the dependencies of the forward-backward (FB) charged-particle multiplicity correlations on the position and width of separate rapidity windows are investigated in proton-proton (non-single diffractive) collisions at s = 0.9, 2.76 and 7 TeV with ALICE at the LHC [56,57]. Our observations on the fluctuations in the forward-backward asymmetry parameter are more or less consistent with the earlier findings [32,34,58].…”

“…For lower energy range at s ≈ 5.0 GeV, this model describes the nature of AB collisions depending on the hadronic degrees of freedom. We can observe collisions between the two particles when the impact parameter b t < s p [34], here σ t denotes the total cross-section, dependent on the species and quantum numbers of the arriving particles as well as the energy s . The relative separation of the two colliding particles is given by b.…”