We analyze measures of the azimuthal asymmetry, in particular the participant harmonic moments, epsilon*, in a variety of Glauber-like models for the early stage of collisions at RHIC. Quantitative comparisons indicate substantial model dependence for epsilon*, reflecting different effective number of sources, while the dependence of the scaled standard deviation sigma(epsilon*)/epsilon* on the particular Glauber model is weak. For all the considered models the values of sigma(epsilon*)/epsilon* range from ~0.5 for the central collisions to ~0.3-0.4 for peripheral collisions. These values, dominated by statistics, change only by 10-15% from model to model. For central collisions and in the absence of correlations between the location of sources we obtain through the use of the central limit theorem the simple analytic formula sigma(epsilon*)/epsilon*(b=0) ~ \sqrt{4/pi-1} ~ 0.52$, independent on the collision energy, mass number, or the number of sources. We investigate the shape-fluctuation effects for jet quenching and find they are important only for very central events. Finally, we list some remarks and predictions from smooth hydrodynamics on higher flow coefficients and their fluctuations, in particular sigma(v_4)/v_4=2 sigma(v_2)/v_2.
Glauber models are used to calculate geometric quantities in the initial state of heavy ion collisions, such as impact parameter, number of participating nucleons and initial eccentricity. Experimental heavy-ion collaboration, in particular at RHIC and LHC, use Glauber Model calculations for various geometric observables. In this document, we describe the assumptions inherent to the approach, and provide an updated implementation (v2) of the Monte Carlo based Glauber Model calculation, which originally was used by the PHOBOS collaboration. The main improvement w.r.t. the earlier version (arXiv…
We discuss multiplicity fluctuations of charged particles produced in nuclear collisions measured event-by-event by the NA49 experiment at CERN SPS within the Glauber Monte Carlo approach. We use the concepts of wounded nucleons and wounded quarks in the mechanism of multiparticle production to characterize multiplicity fluctuations expressed by the scaled variance of multiplicity distribution. Although Wounded Nucleon Model correctly reproduce the centrality dependence of the average multiplicity in Pb+Pb collisions, it completely fails in description of corresponding centrality dependence of…
Initial state anisotropies in ultrarelativistic heavy-ion collisions from the Monte Carlo Glauber model
在重离子碰撞的流体动力学模拟中，初始态的空间各向异性转化为末态粒子分布的动量各向异性。因此，理解初始各向异性的起源和量化它们的不确定性对于从实验数据中提取特定的QCD物质性质（如粘度）非常重要。在这项工作中，我们研究了受伤的核子的方法在Monte Carlo Glauber模型的框架，特别关注的不确定性所产生的碰撞核子对之间的核子-核子相互作用和碰撞核内的核子-核子关联的建模。我们比较了黑盘模型和概率轮廓函数方法的非弹性核子核子相互作用，并研究了初始状态的相关性，使用这些国家的最先进的建模的影响。
Influence of initial fluctuations on geometry measures in relativistic U-U and Cu-Au collisions
在Glauber方法的框架下，我们研究了相对论离子碰撞中初始涨落对63 Cu +197 Au和238 U +238 U初始几何的影响.比较变体的Glauber模型（受伤的核子模型，混合模型，和热点模型），我们表明某些观测值的敏感性，特别是方位角偏心率参数以及相关的主轴方向与傅立叶分量。我们在分析中使用了Glissando。
Initial state anisotropies and their uncertainties in ultrarelativistic heavy-ion collisions from the Monte Carlo Glauber model
在重离子碰撞的流体动力学模拟中，初始态的空间各向异性被转化为末态粒子分布的动量各向异性。因此，在从实验数据中提取特定的QCD物质性质（如粘度）之前，理解初始态各向异性及其不确定性的起源是很重要的。在这项工作中，我们回顾了受伤的核子的方法的基础上的Monte Carlo Glauber模型，特别是图表的不确定性所产生的碰撞核子对和碰撞核内的核子-核子相关性之间的核子-核子相互作用的建模。我们讨论了非弹性核子-核子相互作用的黑盘模型和概率分布函数方法之间的差异，并研究了初始状态相关性的影响，使用国家的最先进的建模这些。
Elliptic and Hexadecapole flow of charged hadron in viscous hydrodynamics with Glauber and Color Glass Condensate initial conditions for Pb-Pb collision at $\sqrt{s_{NN}}$=2.76 TeV
We present ver. 3 of GLISSANDO, a versatile Monte-Carlo generator for Glauber-like models of the initial stages of ultra-relativistic heavy-ion collisions. The present version incorporates the wounded quark model, which is phenomenologically successful in reproducing multiplicities of particle production at RHIC and the LHC. Within this model, one can study the nucleon substructure fluctuation effects, recently explored in p-A collisions. In addition, the code includes the possibility of investigating collisions of light nuclei, such as $^{3}$He and $^{3}$H, or the $α$-clustered $^{7,9}$Be, $^…
Recent studies reveal that at high energies, collisions of small system like $p+p$ gives signatures similar to that widely observed in heavy ion collisions hinting towards a possibility of forming a medium with collective behaviour. With this motivation, we have used the Glauber model, which is traditionally applied to heavy ion collisions, in small system using anisotropic and inhomogeneous density profile of proton and found that the proposed model reproduces the charged particle multiplicity distribution of $p+p$ collisions at LHC energies very well. Collision geometric properties like mean…
Comparison of results from a 2+1D relativistic viscous hydrodynamic model to elliptic and hexadecapole flow of charged hadrons measured in Au-Au collisions at $\sqrt{s_{\rm {NN}}}$ = 200 GeV
In the RHIC Beam Energy Scan program, gold nuclei are collided with different collision energies in the range from few to 62.4 GeV. The goals of the program are to explore the onset of QGP creation, locate the critical point of QCD and study dense baryon matter. We report on the first application of Monte Carlo Glauber (GLISSANDO2) and T$_{\rm R}$ENTo $p=0$ initial states extended to 3D for event-by-event viscous fluid dynamic (vHLLE) with hadronic cascade modelling of Au+Au collisions at $\sqrt{s_{_{\rm NN}}}=27$ and 62.4 GeV, which is the upper region of RHIC BES energies. The initial states…
We study within the Monte Carlo Glauber model the influence of collective quantum effects in the Pb nucleus on the azimuthal anisotropy coefficients $ε_{2,3}$ in Pb+Pb collisions at the LHC energies. To account for the quantum effects, we modify the sampling of the nucleon positions by applying suitable filters that guarantee that the colliding nuclei have the mean squared quadrupole and octupole moments consistent with the ones extracted from the experimental quadrupole and octupole strength functions for the Pb nucleus with the help of the energy weighted sum rule. Our Monte Carlo Glauber mo…
In high energy heavy-ion collisions, the final anisotropic flow coefficients and their corresponding event-plane correlations are considered as the medium evolutional response to the initial geometrical eccentricities and their corresponding participant-plane correlations. We formulate a systematic theoretical analysis to study the hydrodynamical responses concerning higher order effects in Pb+Pb collisions at $\sqrt{s_\text{NN}}=2.76$ TeV by using Monte Carlo Glauber (MC-Glauber) model. To further understand the transformations of the initial participant-plane correlation, we construct a new …
We investigate the fluctuations of anisotropic transverse flow due to the finite number of scatterings in a two-dimensional system of massless particles. Using a set of initial geometries from a Monte Carlo Glauber model, we study how flow coefficients fluctuate about their mean value at the corresponding eccentricity, for several values of the scattering cross section. We also show how the distributions of the second and third event planes of anisotropic flow about the corresponding participant plane in the initial geometry evolve as a function of the mean number of scatterings in the system.
A method for studying initial geometry fluctuations via event plane correlations in heavy ion collisions
提出了一种利用傅里叶分析技术测量重离子碰撞中两个或多个不同阶数事件面的相对方位角分布的方法。分析过程表明，涉及两个和三个事件平面（Phi_n，Phi_m和Phi_h）的相关性。这些分布的傅里叶系数与前人提出的余弦（6Phi_2-6Phi_3）和余弦（Phi_1+2Phi_2-3Phi_3）等修正因子相一致，因此该方法为同时研究这些修正因子提供了一个自然的框架。使用Monte Carlo Glauber模型来模拟Au+Au碰撞与波动的初始几何形状，我们能够确定几个新的两个或三个平面具有相当大的幅度，应该通过实验测量的碰撞。
Pseudorapidity profile of transverse momentum fluctuations in heavy ion collisions
本文研究了相对论重离子碰撞中粒子平均横向流的赝快度关联。本文采用3+1维粘性相对论流体动力学方法，在夸克Glauber Monte Carlo模型的初始条件下，研究了最近在$\sqrt{s_{NN}}=2760$ GeV下Pb+Pb碰撞中横向动量涨落的赝快度关联.我们发现模型预测和数据之间的良好协议。此外，我们还研究了另外两个观测量在不同快度仓中的平均横动量协方差。这些观测值在各种系统学下具有更好的稳定性，从而允许数据和模型之间的鲁棒性比较。横向流-横向流相关系数与不同拟速下的底层集体流相关系数直接相关。伪快度中的$p_T$分解破缺的3-bin测量给出了纵向平均横向流的可能去相关的估计。
Characterization of initial fluctuations for the hydrodynamical description of heavy ion collisions
逐事件波动的初始条件的流体动力学描述的重离子碰撞的特点。我们提出了一个贝塞尔-傅立叶分解的方位角，在横向平面的半径和快度。这允许在所有流体动力学领域的波动，包括能量密度，压力，流体速度，剪切应力和体积粘性压力的完整表征。它的优点是波动可以相对于它们的波长进行排序，并且它们可以在流体动力学形式体系内逐模式传播。然后，事件集合可以根据函数概率分布来表征。对于Monte Carlo Glauber模型的事件系综，我们提供的证据表明，后者接近高斯形式，从而允许一个特别简单的事件分布的表征。
