Conveners
Jets: 1
- Peter Levai (Hungarian Academy of Sciences (HU))
Jets: 2
- John William Harris (Yale University (US))
Jets: 3
- James Nagle (Unknown)
Jets: 4
- Rene Bellwied (University of Houston (US))
Jets: 5
- Xin-Nian Wang (Lawrence Berkeley National Lab. (US))
Ramona Vogt
(LLNL)
20/05/2014, 09:00
Initial State Physics
Contributed Talk
A compilation of predictions for charged hadron, identified light
hadron, quarkonium, photon,
jet and gauge boson production in $p+$Pb collisions at $\sqrt{s_{_{NN}}} = 5$
TeV was made available ahead of the LHC $p+$Pb run [1].
We will compare the predictions to the available
data and comment on the reliablity of the predictions.
[1] J. Albacete {\it et al.}, Int. J. Mod. Phys. E...
Eric Andrew Appelt
(Vanderbilt University (US))
20/05/2014, 09:20
Jets
Contributed Talk
One of the signatures of the strongly interacting medium produced in central PbPb collisions is
the suppression of high-$p_{\rm T}$ jets and charged particles. In order to to disentangle the
initial state and final state effects in heavy ion collisions, the nuclear modification factor
of both jets and of charged-particles in pPb ($R_{\rm pPb}$) and PbPb ($R_{\rm PbPb}$)
collisions are...
Salvatore Aiola
(Yale University (US))
20/05/2014, 09:40
Jets
Contributed Talk
Hard-scattered partons provide an ideal probe for the study of the Quark-Gluon Plasma because they are produced prior to the formation of the QCD medium in heavy-ion collisions. Early measurements conducted at RHIC experiments have provided compelling evidence of jet quenching. In more recent years LHC experiments have confirmed these observations at a higher collisional energy, which allows...
Aaron Angerami
(Columbia University (US))
20/05/2014, 10:00
Jets
Contributed Talk
Highly energetic jets produced in relativistic heavy ion collisions
provide an important tool to study the QCD medium created in these
collisions. These jets suffer energy loss and modification of their
parton shower through interactions with the medium— a phenomenon known
as jet quenching. A generic feature of such energy loss is the
reduction in jet production rates. In this talk, new...
Korinna Christine Zapp
(CERN)
20/05/2014, 10:20
Jets
Contributed Talk
We investigate both the medium-induced modifications of jets and the jet-induced modifications of the medium in heavy ion collisions at LHC energies with JEWEL.
JEWEL is a fully microscopic Monte Carlo event generator for jet evolution in a dense medium relying on perturbative concepts, that can take any model of the medium as input. We present a detailed comparison between a full viscous...
Marco Panero
(IFT UAM/CSIC)
20/05/2014, 11:10
Jets
Contributed Talk
We present a lattice study of the momentum broadening experienced by a hard parton in the quark-gluon plasma. In particular, the contributions to this real-time phenomenon from soft modes are extracted from a set of gauge-invariant operators in a dimensionally reduced effective theory (electrostatic QCD), which can be simulated on a Euclidean lattice. At the temperatures accessible to present...
Petr Balek
(Charles University (CZ))
20/05/2014, 11:30
Jets
Contributed Talk
The measurement of charged particle spectra in heavy ion collisions carries important information about the properties of hot and dense matter created in these interactions. Spectra measured in lead-lead collisions at different centralities can be compared to the proton-proton spectra giving quantitative information about the properties of such matter. Proton-nucleus collisions provide further...
Xin-Nian Wang
(Central China Normal University/Lawrence Berkeley National Lab)
20/05/2014, 11:50
Jets
Contributed Talk
On behalf the JET Collaboration
Within five different approaches to parton propagation and energy loss in dense matter, a phenomenological study of experimental data on suppression of large $p_T$ single inclusive hadrons in heavy-ion collisions at both RHIC and LHC was carried out. The evolution of bulk medium used in the study for parton propagation was given by 2+1D or 3+1D hydrodynamic...
Barbara Betz
(Frankfurt University)
20/05/2014, 12:10
Jets
Contributed Talk
Recent data on the azimuthal and transverse momentum dependence of high-pT pion nuclear modification factors and high-pT elliptic flow in nuclear collisions at RHIC and LHC are analyzed in terms of a generic dE/dx model that interpolates between running coupling pQCD-based models such as CUJET2.0 and AdS/CFT-inspired holographic models. The jet-energy loss models are coupled to state of the...
Dennis Vadimovich Perepelitsa
(Brookhaven National Laboratory (US))
20/05/2014, 12:30
Jets
Contributed Talk
Measurements of reconstructed jets in high-energy proton-nucleus
collisions over a wide rapidity and transverse momentum range are a
fundamental probe of the partonic structure of nuclei. Inclusive jet
production is sensitive to the modification of parton distribution
functions in the high-density nuclear environment. In the forward
direction and at small pT jets may even explore the...
Peter Alan Steinberg
(Brookhaven National Laboratory (US))
20/05/2014, 12:50
Jets
Contributed Talk
ATLAS has measured prompt photon production in sqrt(s_NN) = 2.76 TeV Pb+Pb collisions using data collected in
2011 with an integrated luminosity of 0.14 nb-1. The measurement is performed with a hermetic, longitudinally
segmented calorimeter, which gives excellent spatial and energy resolution, and detailed information about the
shower shape of each measured photon. A multi-parameter...
Xianguo Lu
(Ruprecht-Karls-Universitaet Heidelberg (DE))
20/05/2014, 14:20
Jets
Contributed Talk
Jets are defined in QCD as cascades of consecutive emission of partons from an initial hard scattering. The process of parton showering and subsequent hadronisation is broadly known as fragmentation. Identified particles in the final state provide an enhanced sensitivity to the flavor dependence of fragmentation.
ALICE at the CERN LHC is a general-purpose heavy ion experiment designed to...
Martin Spousta
(Columbia University and Charles University)
20/05/2014, 14:40
Jets
Contributed Talk
Measurements of charged particle fragmentation functions of jets
produced in ultra-relativistic nuclear collisions are expected to
provide insight on the modification of parton showers in the hot and
dense medium created in the collisions. ATLAS has measured jets at
sqrt{sNN}=2.76 TeV in Pb+Pb collisions using data collected during
2011 run and in p+p collisions using 2013 run. Jets were...
Ana Marin
(GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))
20/05/2014, 15:00
Jets
Contributed Talk
The ALICE experiment at LHC performs measurements of neutral meson
inclusive spectra in mid-rapidity
in a wide $p_{\rm T}$ range in pp,
p-Pb and Pb-Pb collisions, as well as correlations between
leading
$\pi^0$ and charged hadrons. Neutral mesons $\pi^0$, $\eta$, $\omega$
are reconstructed via
complementary methods, using the ALICE
electromagnetic calorimeters and by the central...
Xiaoming Zhang
(Lawrence Berkeley National Lab. (US))
20/05/2014, 15:20
Jets
Contributed Talk
Properties of the hot and dense strongly interacting matter created in
ultra-relativistic heavy-ion collisions can be studied using jets.
Hadronization processes occurring in jets are expected to be modified by
the interaction of partons with the medium.
At intermediate $p_{\rm T}$, a strong increase of the baryon/meson ratio
is observed for inclusive light particles produced in...
Abhijit Majumder
(Wayne state university)
20/05/2014, 15:40
Jets
Contributed Talk
Jet modification measurements to date are carried out by comparing a surviving jet, exiting a dense medium, with a vacuum (unmodified) jet at the same energy. We propose an extension to classify jet modification in heavy-ion collisions by also including the jet mass. The mass of a jet, as measured by jet reconstruction algorithms, is intimately connected to the jet's virtuality (or scale),...
Doga Can Gulhan
(Massachusetts Inst. of Technology (US))
21/05/2014, 09:00
Jets
Contributed Talk
A strong modification of jet properties has been observed in central PbPb collisions when compared to the results from pp collisions. To characterize the energy flow, we present the first detailed measurement of the energy flow of quenched jets with the CMS detector. Those new results extend previous measurements to large angle with respect to the quenched jets, using the high statistics pp...
Martin Rybar
(Charles University (CZ))
21/05/2014, 09:20
Jets
Contributed Talk
Highly energetic jets produced in nuclear collisions are considered to
be a direct probe of hot and dense medium created in the
collision. The jet measurements both at LHC and RHIC indicate a
presence of "jet quenching" - strong energy loss of fast partons in
the hot and dense QCD medium. This talk presents study of properties
of the multi-jet production in heavy ion collisions presented...
Joern Putschke
(Wayne State University)
21/05/2014, 09:40
Jets
Contributed Talk
The measurement of fully reconstructed jets in heavy ion collisions
provides unique probes of the Quark-Gluon Plasma (QGP). However, full
jet reconstruction in such events is challenging due to a large
population of combinatorial background "jets" that overwhelm the true
hard jet population by several orders of magnitude. In order to carry
out accurate, data-driven jet measurements...
Mr
Tan Luo
(Central China Normal University)
21/05/2014, 10:00
Jets
Contributed Talk
A Linearized Boltzmann Transport model is developed for the study of parton propagation inside quark-gluon plasma. The leading partons, thermal recoiled partons and radiated gluons are all tracked so that one can also study jet-induced medium excitation. In this study, we implement the complete set of elastic parton scattering processes and investigate parton energy loss, transverse momentum...
Richard Alexander Barbieri
(Massachusetts Inst. of Technology (US))
21/05/2014, 10:20
Jets
Contributed Talk
Studies of dijet and photon-jet properties in pPb collisions are of great importance to
establish a QCD baseline for hadronic interactions with cold nuclear matter. Dijet and
photon-jet production have been measured in pPb collisions at a nucleon-nucleon center-of-mass
energy of 5.02 TeV. The transverse momentum balance and azimuthal angle correlations are studied
in both dijet and...
Kurt Eduard Jung
(Purdue University (US))
21/05/2014, 11:10
Jets
Contributed Talk
The energy loss of jets in heavy-ion collisions is expected to depend on the flavor of the fragmenting parton. Thus, measurements of jet quenching as a function of flavor place powerful constraints on the thermodynamical and transport properties of the hot and dense medium. Measurements of the nuclear modification factors of the heavy-flavor-tagged jets in both PbPb and pPb collisions can...
Dr
Konrad Tywoniuk
(Universitat de Barcelona)
21/05/2014, 11:30
Jets
Contributed Talk
We study the modifications of jets created in heavy-ion collisions at LHC energies. The inherent hierarchy of scales governing the jet evolution allows to distinguish a leading jet structure, which interacts coherently with the medium as a single color charge, from softer sub-structures that will be sensitive to effects of color decoherence. We argue how this separation comes about and show...
32.
Zeroing in on the initial state - tomography combining bulk, jet and electromagnetic observables
Thorsten Renk
(University of Jyväskylä)
21/05/2014, 11:50
Jets
Contributed Talk
One of the unsolved problems in the current 'standard model' of heavy ion physics is the apparent rapid thermalization of QCD matter in the pre-equilibrium stage. While it is challenging to probe this mechanism directly, there are now several observables available which allow tomographic imaging of the initial state geometry, which is expected to carry remnant information of the equilibration...
Krishna Rajagopal
(Massachusetts Inst. of Technology (US))
21/05/2014, 12:10
Jets
Contributed Talk
We present calculations in which a light quark shoots through a finite
slab of strongly coupled $\mathcal{N} = 4 $ supersymmetric Yang-Mills plasma, with thickness $L$,
focussing on what comes out on the other side. We find that even when the "jets'"
that emerge from the plasma have lost a substantial fraction of their energy they
look in almost all respects like "jets" in vacuum with the...
Daniel Pablos
(Universitat de Barcelona)
21/05/2014, 12:30
QCD at High Temperature and/or Density
Contributed Talk
We propose and explore a new hybrid approach to jet energy loss in a strongly coupled medium. The basis of this phenomenological approach is to treat physics processes at different energy scales differently. The high-$Q^2$ processes associated with the QCD evolution of the jet from the hard production up to hadronization are treated perturbatively, following DGLAP evolution, to which we...
Hongxi Xing
(LANL)
21/05/2014, 12:50
New Theoretical Developments
Contributed Talk
There have been a lot of efforts focused on qualitative and quantitative studies of the properties of the sQGP through jet quenching. However, it is not clear whether the properties of the medium such as the jet transport parameter as probed by a propagating jet is unique and intrinsic to the medium, independent of the hard processes that produce the energetic jets. This is a problem of...
yacine mehtar-tani
(IPhT CEA/Saclay)
21/05/2014, 13:10
New Theoretical Developments
Contributed Talk
In the context of the recently derived probabilistic picture of in-medium jet evolution, arXiv:1311.5823 [hep-ph], we study radiative corrections which yield potentially large double logarithms, $\alpha_s ln^2 L$, for large enough medium length $L$ (arXiv:1304.7677 [hep-ph]). We show in particular that, due to a large separation of time scales, these corrections can be reabsorbed in a...
