We present the first global extraction of the jet transport coefficient ($\hat q$) for cold nuclear matter within the framework of higher-twist expansion. The analysis takes into account the world data on transverse momentum broadening in semi-inclusive $e$-A deep inelastic scattering (DIS) and in Drell-Yan dilepton and heavy quarkonium production in $p$-A collisions, as well as the nuclear modification of the structure functions in DIS. The results of this work provide the first quantitative evidence for the universality and non-trivial scale dependence of the medium transport property, similar to that for nucleon structure as encoded in the standard parton distribution functions. We expect the extracted scale dependence of $\hat q$ for cold nuclear matter can be extended to precisely identify the fundamental property of quark gluon plasma.
Within a multi-phase transport model with string melting scenario, jet transport parameter $\hat{q}$ is calculated in Au+Au collisions at $\sqrt{s_{NN} } $= 200 GeV and Pb+Pb collisions at $\sqrt{s_{NN} } $= 2.76 TeV. The $\hat{q}$ increases with the increasing of jet energy for both partonic phase and hadronic phase. The energy and path length dependences of $\hat{q}$ in full heavy-ion evolution are consistent with the expectations of jet quenching. The correlation between jet transport parameter $\hat{q}$ and dijet transverse momentum asymmetry $A_{J}$ is mainly investigated, which discloses…
Nuclear modification factors of single hadrons and dihadrons at large transverse momentum ($p_{\rm T}$) in high-energy heavy-ion collisions are studied in a next-to-leading-order (NLO) perturbative QCD parton model. Parton fragmentation functions (FFs) in $A+A$ collisions are modified due to jet energy loss which is proportional to the jet transport coefficient $\hat{q}$ characterizing the interaction between the parton jet and the produced medium. By confronting 6 current sets of NLO parton FFs for large $p_{\rm T}$ hadron productions, we extract $\hat{q}$ quantitatively via a global fit to d…
Recent measurements of the centrality and rapidity dependence of single inclusive jet production in p+Pb collisions at the LHC have revealed large and non-trivial nuclear modification of the production cross section for this process. In this paper, we explore to what extent such nuclear modification can be understood by the framework of standard cold nuclear matter effects, in particular initial-state cold nuclear matter energy loss. We demonstrate quantitatively that theoretical calculations which include medium-induced radiative corrections can describe rather reasonably the attenuation of t…
Within the framework of the generalized QCD factorization formalism, we perform the first global analysis of the jet transport coefficient ($\hat q$) for cold nuclear matter. The analysis takes into account the world data on transverse momentum broadening in semi-inclusive electron-nucleus deep inelastic scattering, Drell-Yan dilepton and heavy quarkonium production in proton-nucleus collisions, as well as the nuclear modification of the structure functions in deep inelastic scattering, comprising a total of 215 data points from 8 data sets. For the first time, we clarify quantitatively the un…
We present a study of the nuclear-medium induced transverse momentum broadening of particle production in future electron-ion-collision~(EIC) experiments. By considering the multiple scattering between hard partons and cold nuclear medium within the higher-twist factorization framework in perturbative QCD, we calculate the transverse momentum broadening of single hadron production in semi-inclusive measurements, as well as the nuclear enhancement of the transverse momentum imbalance for di-hadron and heavy-meson pair productions. In particular, a kinematics dependent non-perturbative jet trans…
We study the suppressions of high transverse momentum single hadron and dihadron productions in high-energy heavy-ion collisions based on the framework of a next-to-leading-order perturbative QCD parton model combined with the higher-twist energy loss formalism.Our model can provide a consistant description for the nuclear modification factors of single hadron and dihadron productions in central and non-central nucleus-nucleus collisions at RHIC and the LHC energies. We quantitatively extract the value of jet quenching parameter $\hat q$ via a global $χ^2$ analysis, and obtain ${\hat{q}}/{T^3}…
We investigate the cold nuclear matter (CNM) effects on the productions of the isolated prompt photon and $γ+$jet in proton-lead collisions at $\rm 8.16$ TeV under the next-to-leading order (NLO) perturbative quantum chromodynamics calculations with four parametrizations for nuclear parton distribution functions (nPDFs), i.e. DSSZ, EPPS16, nCTEQ15, nIMParton. Our theoretical calculations provide good descriptions of pp baseline in the ATLAS collaboration and make predictions for future experimental results at $\rm p$+$\rm Pb$ collisions. We calculate the dependence of the nuclear modification …
We propose a kinematic method based on a factorization formula for precisely measuring the top quark mass $m_t$ in $pp$ collisions using boosted top jets with light soft drop grooming. By using light grooming, which is an order of magnitude less aggressive than typical grooming, we retain a universal description of the top mass scheme and decay effects, while still effectively removing soft contamination from the top jet. We give field theory results for the hadronization corrections for jets induced by a heavy top quark, showing they are described by a universal hadronic parameter that also a…
In our analysis, we combine event-by-event hydrodynamics, within the EKRT formulation, with jet quenching -ASW Quenching Weights- to obtain high-$p_T$ $R_{\rm AA}$ for charged particles at RHIC and LHC energies for different centralities. By defining a $K$-factor that quantifies the departure of $\hat{q}$ from an ideal estimate, $K = \hat{q}/(2ε^{3/4})$, we fit the single-inclusive experimental data for charged particles. This $K$-factor is larger at RHIC than at the LHC but, surprisingly, it is almost independent of the centrality of the collision.
Heavy quarks created in ultra-relativistic heavy-ion collisions are mostly produced in hard QCD processes during the early stages of the reaction. They interact with the hot and cold nuclear matter throughout the evolution of the medium via semi-hard and soft processes such as energy loss via gluon radiations and collisions. Nuclear modification of heavy flavors in p-A systems provides insight into cold nuclear matter effects such as (anti)shadowing and $k_{T}$-broadening, and serves as a baseline for A-A studies. In addition to that the fully reconstructed heavy-flavor jets provide additional…
We present here an extraction of the jet transport coefficient, $\hat{q}$, using RHIC and LHC single-inclusive high-$p_T$ data for different centralities. We fit a $K$-factor that determines the deviation of this coefficient from an ideal estimate, $K \equiv \hat{q}/(2ε^{3/4})$, where $ε$ is given by hydrodynamic simulations. As obtained already in previous studies, this $K$-factor is found to be larger at RHIC than at the LHC. However it is, unexpectedly, basically no-dependent on the centrality of the collision. Taken at face value this result, the $K$-factor would not depend on local proper…
