Elastic Amplitudes and Observables in pp Scattering

Using a unified analytic representation for the elastic scattering amplitudes of pp scattering valid for all high energy region, the behavior of observables in the LHC collisions in the range $\sqrt{s}$ = 2.76 - 14 TeV is discussed. Similarly to the case of 7 TeV data, the proposed amplitudes give excellent description of the preliminary 8 TeV data. We discuss the expected energy dependence of the observable quantities, and present predictions for the experiments at 2.76, 13 and 14 TeV.Comment: 4 pages, 4 figures Contribution to Proceedings of DIFFRACTION 201

pp Elastic Scattering at LHC Energies

Using a unified analytic representation for the elastic scattering amplitudes of pp scattering valid for all energy region, the behavior of observables in the LHC collisions in the range $\sqrt{s}$= 2.76 - 14 TeV is discussed. Similarly to the case of 7 TeV data, the proposed amplitudes give excellent description of the preliminary 8 TeV data. We discuss the expected energy dependence of the observable quantities, and present predictions for the experiments at 2.76, 13 and 14 TeV.Comment: 16 pages, 17 figure

Effects of nucleus initialization on event-by-event observables

In this work we present a study of the influence of nucleus initializations on the event-by-event elliptic flow coefficient, v2. In most Monte-Carlo models, the initial positions of the nucleons in a nucleus are completely uncorrelated, which can lead to very high density regions. In a simple, yet more realistic model where overlapping of the nucleons is avoided, fluctuations in the initial conditions are reduced. However, v2 distributions are not very sensitive to the initialization choice

Effects of initial state fluctuations in the final state elliptic flow measurements using the NeXSPheRIO model

We present a systematic study of the effects due to initial condition fluctuations in systems formed by heavy-ion collisions using the hydrodynamical simulation code NeXSPheRIO. The study was based on a sample of events generated simulating Au+Au collisions at center of mass energy of 200 GeV per nucleon pair with impact parameter ranging from most central to peripheral collisions. The capability of the NeXSPheRIO code to control and save the initial condition (IC) as well as the final state particles after the 3D hydrodynamical evolution allows for the investigation of the sensitivity of the experimental observables to the characteristics of the early IC. Comparisons of results from simulated events generated using fluctuating initial conditions and smooth initial condition are presented for the experimental observable elliptic flow parameter ($v_2$) as a function of the transverse momentum, $p_t$, and centrality. We compare $v_2$ values estimated using different methods, and how each method responds to effects of fluctuations in the initial condition. Finally, we quantify the flow fluctuations and compare to the fluctuations of the initial eccentricity of the energy density distribution in the transverse plane.Comment: 10 pages, 13 figures, updated version based on PRC referee's comment

Event-plane dependent di-hadron correlations with harmonic vnv_n subtraction in a hydrodynamic model

In this work, a hydrodynamic study of the di-hadron azimuthal correlations for the Au+Au collisions at 200 GeV is carried out. The correlations are evaluated using the ZYAM method for the centrality windows as well as the transverse momentum range in accordance with the existing data. Event-plane dependence of the correlation is obtained after the subtraction of contributions from the most dominant harmonic coefficients. In particular, the contribution from the triangular flow, $v_3$, is removed from the proper correlations following the procedure implemented by the STAR collaboration. The resultant structure observed in the correlations was sometimes attributed to the mini-jet dynamics, but the present calculations show that a pure hydrodynamic model gives a reasonable agreement with the main feature of the published data. A brief discussion on the physical content of the present findings is presented.Comment: 9 pages, 2 figure