Nuclear Theory·nucl-th

Tuesday·September 15, 2015

14 papers—7 primary·7 cross-listed

01
[Submitted on 11 Sept 2015]
Nuclear medium effect on nuclear modification factor of protons and pions in intermediate-energy heavy ion collisions
Ming Lv🇨🇳 · Yu-Gang Ma🇨🇳 · Jin-Hui Chen🇨🇳 · De-Qing Fang🇨🇳 · Guo-Qiang Zhang🇨🇳
Nuclear modification factor ( $R_{c p}$ ) of protons and pions are investigated by simulating Au + Au collisions from 0.8 to 1.8 $A$ GeV in a framework of an isospin-dependent quantum molecular dynamics (IQMD) model. $R_{c p}$ of protons rises with the increase of \pt~ at different beam energies owing to radial flow and Cronin effect. The rate of increase of \rcp~ is suppressed at higher beam energies. The significant difference of $R_{c p}$ between protons and pions indicates different medium effects between protons and pions. By changing the in-medium nucleon-nucleon cross section, the $R_{c p}$ of protons changes a lot, while the $R_{c p}$ of pions does not. Taking the pion absorption into account, the $R_{c p}$ of pions becomes close to unity without $p_{T}$ dependence after deactivating the reaction $π N \to Δ$ , while there is nearly no change on proton. This suggests that the pion absorption plays a dominant role on pion dynamics and have slight effect for proton dynamics.
Comments:
9 pages, 7 figures
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
1509.03676 [pdf]
PRC(2017)·5 citations
02
[Submitted on 11 Sept 2015]
Theory of electromagnetic reactions in light nuclei
Tianrui Xu · Mirko Miorelli · Sonia Bacca · Gaute Hagen
We briefly review the theory for electromagnetic reactions in light nuclei based on the coupled-cluster formulation of the Lorentz integral transform method. Results on photodisintegration reactions of 22O and 40Ca are reported on and preliminary calculations on the Coulomb sum rule for 4He are discussed.
Comments:
6 pages, 5 figures, Proceedings of the 21st international conference on Few-Body Problems in Physics, May 18-22,2015, Chicago (USA)
Subjects:
Nuclear Theory (nucl-th)
arXiv:
1509.03681 [pdf]
0 citations
03
[Submitted on 14 Sept 2015]
Double Lambda He-6 in cluster effective field theory
S.-I. Ando (Sunmoon U.)🇰🇷 · Y. Oh (Kyungpook National U.)🇰🇷
The bound state of \nuclide[6][\Lambda\Lambda]{He} is studied as a three-body ( $ΛΛ α$ ) system in a cluster effective field theory at leading order (LO). We find that the system exhibits the limit cycle which is associated with the formation of bound states called the Efimov states. This implies that the three-body contact interaction should be promoted to LO. The relationship of the binding energy and the $ΛΛ$ scattering length is discussed as well as the role of the scale in this system.
Comments:
4 pages, 2 figures, contribution to 21st International Conference on Few-Body Problems in Physics (FB21), May 18-22, 2015, Chicago, USA; revised version to appear in EPJ Web of Conferences
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
1509.03924 [pdf]
EPJ Web Conf.(2016)·0 citations
04
[Submitted on 14 Sept 2015]
Electromagnetic fields and anomalous transports in heavy-ion collisions --- A pedagogical review
Xu-Guang Huang🇨🇳
The hot and dense matter generated in heavy-ion collisions may contain domains which are not invariant under P and CP transformations. Moreover, heavy-ion collisions can generate extremely strong magnetic fields as well as electric fields. The interplay between the electromagnetic field and triangle anomaly leads to a number of macroscopic quantum phenomena in these P- and CP-odd domains known as the anomalous transports. The purpose of the article is to give a pedagogical review of various properties of the electromagnetic fields, the anomalous transports phenomena, and their experimental signatures in heavy-ion collisions.
Comments:
V2: 52 pages, 19 figures. Figures updated. References updated. Published version
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
1509.04073 [pdf]
Rept.Prog.Phys.(2016)·359 citations
05
[Submitted on 14 Sept 2015]
Reduction of the $K^{*}$ meson abundance in heavy ion collisions
Sungtae Cho🇰🇷 · Su Houng Lee🇰🇷
We study the $K^{*}$ meson reduction in heavy ion collisions by focusing on the hadronic effects on the $K^{*}$ meson abundance. We evaluate the absorption cross sections of the $K^{*}$ and $K$ meson by light mesons in the hadronic matter, and further investigate the variation in the meson abundances for both particles during the hadronic stage of heavy ion collisions. We show how the interplay between the interaction of the $K^{*}$ meson and kaon with light mesons in the hadronic medium determines the final yield difference of the statistical hadronization model to the experimental measurements. For the central Au+Au collision at $s_{N N} = 200$ GeV, we find that the $K^{*} / K$ yield ratio at chemical freeze-out decreases by $36%$ during the expansion of the hadronic matter, resulting in the final ratio comparable to STAR measurements of 0.23 $\pm 0.05$ .
Comments:
12 pages, 8 figures
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
1509.04092 [pdf]
PRC(2018)·27 citations
06
[Submitted on 14 Sept 2015]
Pseudorapidity correlations in heavy ion collisions from viscous fluid dynamics
Akihiko Monnai🇺🇸 · Bjoern Schenke🇺🇸
We demonstrate by explicit calculations in 3+1 dimensional viscous relativistic fluid dynamics how two-particle pseudorapidity correlation functions in heavy ion collisions at the LHC and RHIC depend on the number of particle producing sources and the transport properties of the produced medium. In particular, we present results for the Legendre coefficients of the two-particle pseudorapidity correlation function in Pb+Pb collisions at 2760 GeV and Au+Au collisions at 200 GeV from viscous hydrodynamics with three dimensionally fluctuating initial conditions. Our results suggest that these coefficients provide important constraints on initial state fluctuations and the transport properties of the quark gluon plasma.
Comments:
5 pages, 5 figures, Corrected Eq.(8) and all figures to agree with the corrected definition used by ATLAS, conclusions remain unchanged, added references
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
1509.04103 [pdf]
PLB(2016)·43 citations
07
[Submitted on 14 Sept 2015]
Two-particle correlations in pseudorapidity in a hydrodynamic model
Piotr Bozek🇵🇱 · Wojciech Broniowski🇵🇱 · Adam Olszewski🇵🇱
Two-particle pseudorapidity correlations of hadrons produced in Pb+Pb collisions at 2.76 TeV at the CERN Large Hadron Collider are analyzed in the framework of a model based on viscous 3+1-dimensional hydrodynamics with the Glauber initial condition. Based on our results, we argue that the correlation from resonance decays, formed at a late stage of the evolution, produce significant effects. In particular, their contribution to the event averages of the coefficients of the expansion in the Legendre basis explain 60-70% of the experimental values. We have proposed an accurate way to compute these <a_n a_m> coefficients, independent of the binning in pseudorapidity, and tested a double expansion of the two-particle correlation function in the azimuth and pseudorapidity, which allows us to investigate the pseudorapidity correlations between harmonics of the collective flow. In our model, these quantities are also dominated by non-flow effects from the resonance decays. Finally, our method can be used to compute higher-order cumulants for the expansion in orthonormal polynomials which offers a suitable way of eliminating the non-flow effects from the correlation analyses.
Comments:
Editorial corrections
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
1509.04124 [pdf]
PRC(2015)·21 citations

Affiliations

first authorsco-authorsvia INSPIRE

Nuclear medium effect on nuclear modification factor of protons and pions in intermediate-energy heavy ion collisions

Theory of electromagnetic reactions in light nuclei

Double Lambda He-6 in cluster effective field theory

Electromagnetic fields and anomalous transports in heavy-ion collisions --- A pedagogical review

Reduction of the K∗ meson abundance in heavy ion collisions

Pseudorapidity correlations in heavy ion collisions from viscous fluid dynamics

Two-particle correlations in pseudorapidity in a hydrodynamic model

Affiliations

Reduction of the $K^{*}$ meson abundance in heavy ion collisions