A Fourier-cumulant analysis for multiharmonic flow fluctuation

AbstractThe Fourier analysis of the final particle distribution followed by cumulant study of the Fourier coefficient event-by-event fluctuation is one of the main approaches for testing the collective evolution in the heavy-ion collision. Using a multidimensional generating function, we propose a method to extract any possible cumulant of multiharmonic flow fluctuations and classify them in terms of the order of cumulants and harmonics involved in them. In particular, we show that there are 33 distinct cumulants with order 2, 3, 4, 5 and harmonics 2, 3, 4, 5. We compute the normalized version of these cumulants from hydrodynamic simulation for Pb–Pb collisions based on $$_\mathtt{R}$$ R ++. We compare the simulation with those normalized cumulants that the LHC has measured and predict the unmeasured ones. Comparing the initial and final state fluctuation normalized cumulants, we compute the linear and nonlinear hydrodynamic response couplings. We finally introduce the genuine three-particle correlation function containing information of all third-order cumulants.

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Study of the influence of initial-state fluctuations on hydrodynamic simulations

EPJ Web of Conferences ◽

10.1051/epjconf/202024506005 ◽

2020 ◽

Vol 245 ◽

pp. 06005

Author(s):

Marcin Słodkowski ◽

Patryk Gawryszewski ◽

Dominik Setniewski

Keyword(s):

Initial Conditions ◽

Graphics Processing Unit ◽

Heavy Ion ◽

Processing Unit ◽

Initial State ◽

Final State ◽

Hydrodynamic Simulation ◽

Hydrodynamic Simulations ◽

Cartesian Coordinate ◽

Ion Collision

In this work, we are focusing on assessing the contribution of the initial-state fluctuations of heavy ion collision in the hydrodynamic simulations. We are trying to answer the question of whether the hydrodynamic simulation retains the same level of fluctuation in the final-state as for the initial stage. In another scenario, the hydrodynamic simulations of the fluctuation drowns in the final distribution of expanding matter. For this purpose, we prepared sufficient relativistic hydrodynamic program to study A+A interaction which allows analysing initial-state fluctuations in the bulk nuclear matter. For such an assumption, it is better to use high spatial resolution. Therefore, we applied the (3+1) dimensional Cartesian coordinate system. We implemented our program using parallel computing on graphics cards processors - Graphics Processing Unit (GPU). Simulations were carried out with various levels of fluctuation in initial conditions using the average method of events coming from UrQMD models. Energy density distributions were analysed and the contribution of fluctuations in initial conditions was assessed in the hydrodynamic simulation.

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TWO- AND MULTI-PARTICLE CORRELATIONS: ACCESS TO DYNAMICS AND STRUCTURE OF NUCLEAR SYSTEMS

International Journal of Modern Physics E ◽

10.1142/s0218301308010787 ◽

2008 ◽

Vol 17 (09) ◽

pp. 1790-1798

Author(s):

GIUSEPPE VERDE

Keyword(s):

Heavy Ion ◽

Heavy Ion Collision ◽

Particle Correlation ◽

Particle Correlations ◽

Nuclear Systems ◽

Ion Collision

Results from particle correlation measured in heavy-ion collision experiments are shown. Information about dynamics of the reaction as well as and spectroscopy of unbound nuclear systems can be extracted, offering important opportunities for future experiments with exotic nuclear beams.

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RAPIDITY CORRELATIONS IN PARTICLES PRODUCED IN INELASTIC COLLISIONS OF 12C AND 28Si IONS IN EMULSION AT 4.5A GeV/c

International Journal of Modern Physics E ◽

10.1142/s0218301392000382 ◽

1992 ◽

Vol 01 (04) ◽

pp. 859-870 ◽

Cited By ~ 6

Author(s):

M. TARIQ ◽

M. ZAFAR ◽

S. AHMAD

Keyword(s):

Correlation Functions ◽

Heavy Ion ◽

Inelastic Collisions ◽

Heavy Ion Collision ◽

Particle Correlation ◽

Ion Interactions ◽

Zero Correlation ◽

Rapidity Gap ◽

Ion Collision

Correlations between particles produced in the interactions of 28 Si and 12 C nuclei with emulsion nuclei at 4.5A GeV/c has been investigated. 701 events of 28 Si and 844 of 12 C interactions have been analysed. A method which combines techniques from the method of using the two-particle correlation functions and from rapidity-gap distributions is applied. This method has been used successfully by others to study the correlation in P-Em and light-ion interactions. However, we have applied it to the heavy-ion collision data. Small but significant departure from zero-correlation is observed.

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Two-particle correlations on transverse momentum: an untapped resource for studying relativistic heavy-ion collision dynamics

EPJ Web of Conferences ◽

10.1051/epjconf/202023501003 ◽

2020 ◽

Vol 235 ◽

pp. 01003

Author(s):

Robert L. Ray ◽

Alexander M. Jentsch

Keyword(s):

Transverse Momentum ◽

Heavy Ion ◽

Heavy Ion Collision ◽

Collision Dynamics ◽

Particle Correlation ◽

Angular Correlations ◽

Relativistic Heavy Ion Collision ◽

Theoretical Predictions ◽

Ion Collision ◽

Untapped Resource

Two-particle correlation projections onto two-dimensional transverse momentum coordinates (pt1, pt2) allow access to properties of the relativistic heavy-ion collision system which are complementary to that studied using angular correlations. Examples include the degree of thermal equilibration and the variance of dynamical fluctuations in hard-scattering processes. Results for minimum-bias Au + Au collisions at √sNN = 200 are presented, with the structures described by two phenomenological models. The correlations structures and extracted physical quantities are then compared to theoretical predictions. Conclusions from these comparisons regarding global equilibration, fluctuations in soft and semi-hard QCD processes, and the effects of the hot, dense collision medium are presented.

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Event-by-event shape and flow fluctuations of relativistic heavy-ion collision fireballs

Physical Review C ◽

10.1103/physrevc.84.024911 ◽

2011 ◽

Vol 84 (2) ◽

Cited By ~ 214

Author(s):

Zhi Qiu ◽

Ulrich Heinz

Keyword(s):

Heavy Ion ◽

Event Shape ◽

Heavy Ion Collision ◽

Relativistic Heavy Ion Collision ◽

Flow Fluctuations ◽

Ion Collision

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TWO-PARTICLE CORRELATION IN HEAVY-ION COLLISIONS AT CSR ENERGY

International Journal of Modern Physics E ◽

10.1142/s0218301307007684 ◽

2007 ◽

Vol 16 (07n08) ◽

pp. 2200-2204

Author(s):

JINGBO ZHANG ◽

QICHUN FENG ◽

LEI HUO ◽

WEINING ZHANG

Keyword(s):

Imaging Technique ◽

Final State Interaction ◽

Relativistic Quantum ◽

Heavy Ion ◽

Quantum Molecular Dynamics ◽

Dynamics Model ◽

Final State ◽

Particle Correlation ◽

Ion Collisions ◽

The Relationship

The predictions of the two-particle correlation by using the relativistic quantum molecular dynamics model are presented for the heavy-ion reactions at HIRFL-CSR energy. The two-proton correlation function with the final state interaction is calculated with the Lednicky code for the U + U collisions at beam energy 520 A MeV. Applying the imaging technique, the relationship between the freeze-out spatial distributions and the results of correlation femtoscopy is investigated. We find that one can reliably reconstruct the source functions from the two-particle correlation functions with ignoring the degree of space-momentum correlations at this energy. The results are useful to the designing the hadron detector at CSR.

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PROSPECTS OF SEARCHING FOR (UN)PARTICLES FROM HIDDEN SECTORS USING RAPIDITY CORRELATIONS IN MULTIPARTICLE PRODUCTION AT THE LHC

International Journal of Modern Physics A ◽

10.1142/s0217751x09045820 ◽

2009 ◽

Vol 24 (24) ◽

pp. 4529-4572 ◽

Cited By ~ 11

Author(s):

MIGUEL-ANGEL SANCHIS-LOZANO

Keyword(s):

Heavy Ion ◽

Gluon Plasma ◽

New Physics ◽

Event Shape ◽

Final State ◽

Factorial Moments ◽

Particle Correlation ◽

Ion Collisions ◽

Simplifying Assumptions ◽

The Impact

Most signatures of new physics have been studied on the transverse plane with respect to the beam direction at the LHC where background is much reduced. In this paper we propose the analysis of inclusive longitudinal (pseudo)rapidity correlations among final-state (charged) particles in order to search for (un)particles belonging to a hidden sector beyond the Standard Model, using a selected sample of p–p minimum bias events (applying appropriate off-line cuts on events based on, e.g. minijets, high-multiplicity, event shape variables, high-p⊥ leptons and photons, etc.) collected at the early running of the LHC. To this aim, we examine inclusive and semi-inclusive two-particle correlation functions, forward–backward correlations, and factorial moments of the multiplicity distribution, without resorting to any particular model but under very general (though simplifying) assumptions. Finally, motivated by some analysis techniques employed in the search for quark–gluon plasma in heavy-ion collisions, we investigate the impact of such intermediate (un)particle stuff on the (multi)fractality of parton cascades in p–p collisions, by means of a Lévy stable law description and a Ginzburg–Landau model of phase transitions. Results from our preliminary study seem encouraging for possible dedicated analyses at LHC and Tevatron experiments.

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