scholarly journals Probing jet medium interactions via Z(H) + jet momentum imbalances

2020 ◽  
Vol 80 (12) ◽  
Author(s):  
Lin Chen ◽  
Shu-Yi Wei ◽  
Han-Zhong Zhang

AbstractDifferent types of high energy hard probes are used to extract the jet transport properties of the Quark-Gluon Plasma created in heavy-ion collisions, of which the heavy boson tagged jets are undoubtedly the most sophisticated due to its clean decay signature and production mechanism. In this study, we used the resummation improved pQCD approach with high order correction in the hard factor to calculate the momentum ratio $$x_J$$ x J distributions of Z and Higgs (H) tagged jets. We found that the formalism can provide a good description of the 5.02 TeV pp data. Using the BDMPS energy loss formalism, along with the OSU 2 + 1D hydro to simulate the effect of the medium, we extracted the value of the jet transport coefficient to be around $${\hat{q}}_0=4\sim 8~\text {GeV}^2/\text {fm}$$ q ^ 0 = 4 ∼ 8 GeV 2 / fm by comparing with the Z + jet PbPb experimental data. The H + jet $$x_J$$ x J distribution were calculated in a similar manner in contrast and found to have a stronger Sudakov effect as compared with the Z + jet distribution. This study uses a clean color-neutral boson as trigger to study the jet quenching effect and serves as a complimentary method in the extraction of the QGP’s transport coefficient in high energy nuclear collisions.

2015 ◽  
Vol 24 (02) ◽  
pp. 1530001 ◽  
Author(s):  
Guang-You Qin

The exploration of the strong-interaction matter under extreme conditions is one of the main goals of relativistic heavy-ion collisions. We provide some of the main results on the novel properties of quark-gluon plasma, with particular focus given to the strong collectivity and the color opaqueness exhibited by such hot and dense matter produced in high-energy nuclear collisions at RHIC and the LHC.


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
T. Niida ◽  
Y. Miake

AbstractThe progress over the 30 years since the first high-energy heavy-ion collisions at the BNL-AGS and CERN-SPS has been truly remarkable. Rigorous experimental and theoretical studies have revealed a new state of the matter in heavy-ion collisions, the quark-gluon plasma (QGP). Many signatures supporting the formation of the QGP have been reported. Among them are jet quenching, the non-viscous flow, direct photons, and Debye screening effects. In this article, selected signatures of the QGP observed at RHIC and the LHC are reviewed.


2019 ◽  
Vol 206 ◽  
pp. 04004 ◽  
Author(s):  
Ben-Wei Zhang ◽  
Guo-Yang Ma ◽  
Wei Dai ◽  
Sa Wang ◽  
Shan-Liang Zhang

When an energetic parton traversing the QCD medium, it may suffer multiple scatterings and lose energy. This jet quenching phenomenon may lead to the suppression of leading hadron productions as well as medium modifications of full jet observables in heavy-ion collisions. In this talk we discuss the nuclear modificationfactors and yield ratios of identified meson such as η, ρ0, φ, ω, and $ K_{\rm{S}}^0 $ as well as π meson at large pT in A+A collisions at the next to-leading order (NLO) with high-twist approach of parton energy loss. Then we discuss a newly developed formalism of combing NLO matrix elements and parton shower (PS) for initial hard production with parton energy loss in the QGP, and its application in investigating massivegauge boson(Z0/W±)tagged jet productions and b $ \bar {b} $ dijet correlations in Pb+Pb at the LHC.


Open Physics ◽  
2012 ◽  
Vol 10 (6) ◽  
Author(s):  
ShinIchi Esumi

AbstractAzimuthal event anisotropy and particle correlation have been used to analyze the collectivity of the system created in the high-energy heavy-ion collisions in order to study the properties of Quark Gluon Plasma (QGP). Higher harmonic event anisotropy is recently recognized to carry the information of initial participant geometrical fluctuation because of the finite number of participating nucleons in heavy-ion collisions. The system response after the collective expansion can be observed as higher harmonic event anisotropy, the n-th harmonic order dependence can be used to further constrain the hydro-dynamical properties of the system. The multi-particle azimuthal correlation with respect to the higher harmonic event plane can be used as a tool to understand the origin of the higher harmonic event anisotropy and its relation to the medium response from the jet-quenching as soft-hard interplay. Recent results on the higher harmonic event anisotropy measurements and an attempt of two-particle correlation analysis with respect to the higher harmonic event planes are discussed.


2018 ◽  
Vol 172 ◽  
pp. 05010 ◽  
Author(s):  
Christine Nattrass

The Quark Gluon Plasma (QGP) is created in high energy heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC). This medium is transparent to electromagnetic probes but nearly opaque to colored probes. Hard partons produced early in the collision fragment and hadronize into a collimated spray of particles called a jet. The partons lose energy as they traverse the medium, a process called jet quenching. Most of the lost energy is still correlated with the parent parton, contributing to particle production at larger angles and lower momenta relative to the parent parton than in proton-proton collisions. This partonic energy loss can be measured through several observables, each of which give different insights into the degree and mechanism of energy loss. The measurements to date are summarized and the path forward is discussed.


2015 ◽  
Vol 24 (11) ◽  
pp. 1530014 ◽  
Author(s):  
Guang-You Qin ◽  
Xin-Nian Wang

Jet quenching in high-energy heavy-ion collisions can be used to probe properties of hot and dense quark–gluon plasma. We provide a brief introduction to the concept and framework for the study of jet quenching. Different approaches and implementation of multiple scattering and parton energy loss are discussed. Recent progresses in the theoretical and phenomenological studies of jet quenching in heavy-ion collisions at RHIC and LHC are reviewed.


2021 ◽  
Vol 2103 (1) ◽  
pp. 012134
Author(s):  
V S Borisov ◽  
A Ya Berdnikov ◽  
Ya A Berdnikov ◽  
D O Kotov ◽  
Iu M Mitrankov

Abstract The study of deconfinement state of nuclear matter called quark-gluon plasma (QGP) and phase transition of QGP to hadronic gas is the main goal of high energy physics. Some of the important signatures of QGP formation in heavy-ion collisions include strangeness enhancement at intermediate values of the transverse momentum (ρT ) and a jet quenching effect at high ρT values. Nuclear modification factors (RAB ) for light hadrons are used to quantify these effects. The K *0 and φ mesons can serve as a good probes to investigate QGP properties, because these mesons contain (anti)strange quark and its yields can be measured in a wide ρT range. Comparison of experimental data with theoretical model calculations is important for understanding the evolution of heavy-ion collision. One of the most commonly used event generators to describe experimental results of collider experiments is Pythia8. This paper shows, that Pythia8 predicts RAB values of K *0 and φ less than RAB values in experimental data. Consequently, additional (hidden)strange particle production mechanisms are involved.


2007 ◽  
Vol 16 (10) ◽  
pp. 3185-3192 ◽  
Author(s):  
HANZHONG ZHANG ◽  
ENKE WANG

The azimuthal anisotropy of high pT hadron in high energy A + A collisions is studied within the next-to-leading order (NLO) perturbative QCD parton model. The effect of jet quenching is incorporated via a model for modified jet fragmentation functions due to radiative parton energy loss in dense medium. Because NLO contributions behave with stronger quenching effect than LO contributions, the NLO elliptic flow parameter is found to be larger than the LO in the medium pT region.


2014 ◽  
Vol 90 (1) ◽  
Author(s):  
Karen M. Burke ◽  
Alessandro Buzzatti ◽  
Ningbo Chang ◽  
Charles Gale ◽  
Miklos Gyulassy ◽  
...  

2016 ◽  
Vol 2016 ◽  
pp. 1-16 ◽  
Author(s):  
Subhash Singha ◽  
Prashanth Shanmuganathan ◽  
Declan Keane

We review topics related to the first moment of azimuthal anisotropy (v1), commonly known as directed flow, focusing on both charged particles and identified particles from heavy-ion collisions. Beam energies from the highest available, at the CERN LHC, down to projectile kinetic energies per nucleon of a few GeV per nucleon, as studied in experiments at the Brookhaven AGS, fall within our scope. We focus on experimental measurements and on theoretical work where direct comparisons with experiment have been emphasized. The physics addressed or potentially addressed by this review topic includes the study of Quark Gluon Plasma and, more generally, investigation of the Quantum Chromodynamics phase diagram and the equation of state describing the accessible phases.


Sign in / Sign up

Export Citation Format

Share Document