Mon·Aug 17, 2015Monday·August 17, 2015

1. 01*

   Anisotropic distributions in a multi-phase transport model

   You Zhou🇩🇰 · Kai Xiao🇨🇳 · Zhao Feng🇨🇳 · Feng Liu🇨🇳 · Raimond Snellings🇳🇱

   With A Multi-Phase Transport (AMPT) model we investigate the relation between the magnitude, fluctuations and correlations of the initial state spatial anisotropy ${\epsilon }_n$ and the final state anisotropic flow coefficients $v_n$ in Au+Au collisions at $\sqrt{s_{{}_{\mathrm{NN}}}}=$ 200 GeV. It is found that the relative eccentricity fluctuations in AMPT account for the observed elliptic flow fluctuations, in agreement with measurements of the STAR collaboration. In addition, the studies based on 2- and multi-particle correlations and event-by-event distributions of the anisotropies suggest that the Elliptic-Power function is a promising candidate of the underlying probability density function of the event-by-event distributions of ${\epsilon }_n$ as well as $v_n$. Furthermore, the correlations between different order symmetry planes and harmonics in the initial coordinate space and final state momentum space are presented. Non-zero values of these correlations have been observed. The comparison between our calculations and data will, in the future, shed new insight into the nature of the fluctuations of the Quark-Gluon Plasma produced in heavy ion collisions.

   nucl-exnucl-thPRC(2016)·44 citations
2. 02*

   Intrinsic Fluctuations of the Proton Saturation Momentum Scale in High Multiplicity p+p Collisions

   Larry McLerran🇺🇸 · Prithwish Tribedy🇺🇸

   High multiplicity events in p+p collisions are studied using the theory of the Color Glass Condensate. We show that intrinsic fluctuations of the proton saturation momentum scale are needed in addition to the sub-nucleonic color charge fluctuations to explain the very high multiplicity tail of distributions in p+p collisions. The origin of such intrinsic fluctuations are presumably non-perturbative in nature. Classical Yang Mills simulations using the IP-Glasma model are performed to make quantitative estimations. We find that fluctuations as large as $\mathcal{O}$(1) of the average values of the saturation momentum scale can lead to rare high multiplicity events seen in p+p data at RHIC and LHC energies. Using the available data on multiplicity distributions we try to constrain the distribution of the proton saturation momentum scale and make predictions for the multiplicity distribution in 13 TeV p+p collisions.

   ↳ hep-phhep-exnucl-exnucl-thNPA(2016)·66 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.