Nuclear Theory·nucl-th

Friday·January 25, 2019

6 papers—3 primary·3 cross-listed

01
Hybrid Hadronization
Rainer J. Fries🇺🇸 · Michael Kordell🇺🇸
We discuss Hybrid Hadronization, a hadronization model which interpolates between string fragmentation in dilute parton systems and quark recombination in dense parton systems. We lay out the basic principles, discuss some details of the implementation, and show some prelimiary results. Hybrid Hadronization is realized as a software package which works with PYTHIA 8 and will be released publicly in the near future.
nucl-thhep-phPoS(2019)·10 citations
02
Strangeness Enhancement in p+p, p+Pb and Pb+Pb Collisions at LHC Energies
Y. Kanakubo🇯🇵 · M. Okai🇯🇵 · Y. Tachibana🇺🇸 · T. Hirano🇯🇵
We investigate whether the quark gluon plasma (QGP) is created in small colliding systems from analyses of various hadron yields and their ratios in proton-proton (p+p), proton-lead (p+Pb) and lead-lead (Pb+Pb) collisions at LHC energies. Recently, the ALICE Collaboration reports enhancement of yield ratio of multi-strange hadrons to charged pions as a function of multiplicity at mid-rapidity. Motivated by these results, we develop the dynamical core-corona initialization framework and find that our results describe tendencies of the ALICE data especially for multi-strange hadrons. These results indicate that the QGP is partly formed in high multiplicity events in small colliding systems.
nucl-thhep-phnucl-exJPS Conf.Proc.(2019)·3 citations
03
Relativistic dissipation obeys Chapman-Enskog asymptotics: analytical and numerical evidence as a basis for accurate kinetic simulations
A. Gabbana · D. Simeoni · S. Succi · R. Tripiccione
We present an analytical derivation of the transport coefficients of a relativistic gas in (2+1) dimensions for both Chapman-Enskog (CE) asymptotics and Grad's expansion methods. Moreover, we develop a systematic calibration method, connecting the relaxation time of relativistic kinetic theory to the transport parameters of the associated dissipative hydrodynamic equations. Comparison between the analytical results and numerical simulations, shows that the CE method correctly captures dissipative effects, while Grad's method does not. The resulting calibration procedure based on the CE method opens the way to the quantitative kinetic description of dissipative relativistic fluid dynamics under fairly general conditions, namely flows with strongly non-linearities, in non-ideal geometries, across both ultra-relativistic and near-non-relativistic regimes.
nucl-thphysics.comp-phphysics.flu-dynPRE(2019)·8 citations
04
Azimuthal harmonics in small and large collision systems at RHIC top energies
STAR Collaboration: J. Adam🇺🇸 · L. Adamczyk🇵🇱 · J. R. Adams🇺🇸 · J. K. Adkins🇺🇸 · G. Agakishiev🇷🇺 · M. M. Aggarwal🇮🇳 · Z. Ahammed🇮🇳 · I. Alekseev🇷🇺 · D. M. Anderson🇺🇸 · R. Aoyama🇯🇵 · A. Aparin🇷🇺 · D. Arkhipkin🇺🇸 and 331 other authors
The first ( $v_{1}^{even}$ ), second ( $v_{2}$ ) and third ( $v_{3}$ ) harmonic coefficients of the azimuthal particle distribution at mid-rapidity, are extracted for charged hadrons and studied as a function of transverse momentum ( $p_{T}$ ) and mean charged particle multiplicity density $⟨ N_{ch} ⟩$ in U+U ( $\roots = 193$ ~GeV), Au+Au, Cu+Au, Cu+Cu, $d$ +Au and $p$ +Au collisions at $\roots = 200$ ~GeV with the STAR Detector. For the same $⟨ N_{ch} ⟩$ , the $v_{1}^{even}$ and $v_{3}$ coefficients are observed to be independent of collision system, while $v_{2}$ exhibits such a scaling only when normalized by the initial-state eccentricity ( $ε_{2}$ ). The data also show that $ln (v_{2} / ε_{2})$ scales linearly with $⟨ N_{ch} ⟩^{- 1/3}$ . These measurements provide insight into initial-geometry fluctuations and the role of viscous hydrodynamic attenuation on $v_{n}$ from small to large collision systems.
↳ nucl-exnucl-thPRL(2019)·71 citations
05
A short review on recent developments in TMD factorization and implementation
Ignazio Scimemi🇪🇸
In the latest years the theoretical and phenomenological advances in the factorization of several collider processes using the transverse momentum dependent distributions (TMD)has greatly increased. I attempt here a short resume of the newest developments discussing also the most recent perturbative QCD calculations. The work is not strictly directed to experts in the field and it wants to offer an overview of the tools and concepts which are behind the TMD factorization and evolution. I consider both theoretical and phenomenological aspects, some of which have still to be fully explored. It is expected that actual colliders and the Electron Ion Collider (EIC) will provide important information in this respect.
↳ hep-phhep-exhep-latnucl-thAdv.High Energy Phys.(2019)·20 citations
06
Heavy ion jet physics studies using precision jet substructure and quark-gluon jet classification
Yang-Ting Chien🇺🇸
In the first talk I discuss the usefulness of jet grooming for testing jet quenching mechanisms, and I present a calculation of soft-drop jet mass distribution in proton-proton and heavy ion collisions. In the second talk I discuss the comprehensive studies of quark and gluon jet substructure as a way to search for qualitatively new jet modification signatures. I emphasize the importance of precise understanding of jet substructure as well as powerful analysis tools in future heavy ion jet physics studies, with direct applications to hard probes using heavy flavors and hadronically-decaying electroweak bosons.
↳ hep-phhep-exnucl-exnucl-thPoS(2019)·1 citation

Affiliations

first authorsco-authorsvia INSPIRE

Hybrid Hadronization

Strangeness Enhancement in p+p, p+Pb and Pb+Pb Collisions at LHC Energies

Relativistic dissipation obeys Chapman-Enskog asymptotics: analytical and numerical evidence as a basis for accurate kinetic simulations

Azimuthal harmonics in small and large collision systems at RHIC top energies

A short review on recent developments in TMD factorization and implementation

Heavy ion jet physics studies using precision jet substructure and quark-gluon jet classification

Affiliations