Conveners
Initial state physics: 1
- Carlos Pajares (University Santiago de Compostela)
Initial state physics: 2
- Kari J. Eskola (University of Jyvaskyla)
Raju Venugopalan
19/05/2014, 11:00
Initial State Physics
Contributed Talk
The ridge in pp, p/d+A and A+A collisions manifest at very high multiplicities. Regardless of whether initial state or final state effects dominate, the physics of very high parton densities is relevant. In this talk, we attempt a synthesis of the state-of-the art in the CGC approach to computing both initial state and final state effects that generate collimated long range rapidity...
Kevin Dusling
19/05/2014, 11:20
Initial State Physics
Contributed Talk
We explore the detailed structure of the {\em ridge} in the Color-Glass-Condensate (CGC) effective field theory of QCD and demonstrate a novel mechanism that produces a non-vanishing $v_3$ without final-state re-scattering. A $v_3$ in agreement with the LHC p+Pb data is generated by the interference of diagrams attributed to the jet (away-side) and ridge (near-side) substructure of the...
Prithwish Tribedy
(VECC)
19/05/2014, 11:40
Initial State Physics
Contributed Talk
The IP-Glasma model of initial conditions based on the *ab initio* color glass condensate (CGC) framework successfully explains the bulk features of global data for various systems like p+p, p+A and A+A over a wide range of energies [1-3]. We employ this framework to study deformed U+U collisions, asymmetric Cu+Au collisions and the effect of deformation in Au+Au collisions at RHIC. A...
Hui Wang
(Brookhaven National Lab)
19/05/2014, 12:00
Initial State Physics
Contributed Talk
The azimuthal anisotropy of particle production is commonly used in high-energy nuclear collisions to study the early evolution of the expanding system. The prolate shape of uranium nuclei provides the possibility to study how the initial geometry of the nuclei affects the azimuthal distributions. It also provides a unique opportunity to understand the initial conditions for particle...
Joakim Nystrand
(University of Bergen (NO))
19/05/2014, 12:20
Initial State Physics
Contributed Talk
Vector mesons are copiously produced in ultra-peripheral
nucleus-nucleus collisions. In these collisions, the nuclei are
separated by impact parameters larger than the sum of the nuclear
radii, and the interaction is mediated by the electromagnetic
field. The interaction effectively corresponds to a photonuclear
interaction between a photon, generated from the electromagnetic field
of...
David d'Enterria
(CERN)
19/05/2014, 12:40
Initial State Physics
Contributed Talk
We have derived a simple generic expression to compute the cross sections for double-parton scatterings
(DPS) in high-energy proton-nucleus and nucleus-nucleus collisions as a function of the
corresponding single-parton hard cross sections [1,2]. Estimates of DPS contributions at LHC energies for
(i) same-sign W-boson pair production in p-Pb, and (ii) double-J/$\psi$ production in Pb-Pb,...
Michael Linus Knichel
(GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))
19/05/2014, 16:30
Initial State Physics
Contributed Talk
Light flavor transverse momentum spectra at intermediate and high $p_{\rm T}$
are important as baseline perturbative QCD measurements in pp, evaluating
initial state effects (nuclear p.d.f.'s) in p-Pb, and for investigating the
suppression in Pb-Pb collisions. In this talk results for all these
collisional systems will be presented.
The new measurement of $R_{\rm pPb}$ for unidentified...
Dr
Alberica Toia
(Johann-Wolfgang-Goethe Univ. (DE))
19/05/2014, 16:50
Initial State Physics
Contributed Talk
Measurements of particle production in proton-nucleus collisions
provide a reference to disentangle final state effects,
i.e. signatures of the formation of a deconfined hot medium, from
initial state effects, already present in cold nuclear matter. While
most of the benchmarks from the control experiment indicate that
initial state effects do not play a role in the observed...
Mauricio Martinez Guerrero
(The Ohio State University)
19/05/2014, 17:10
Initial State Physics
Contributed Talk
We study medium modifications to the interference pattern between initial and final state radiation. We compute single gluon production off a highly energetic parton that undergoes a hard scattering and subsequently crosses a dense QCD medium of finite size. Multiple soft scatterings with the medium are resumed within the harmonic oscillator approximation. We find the decoherence of correlated...
Li Yi
19/05/2014, 17:30
Initial State Physics
Contributed Talk
Long-range pseudo-rapidity ($\Delta\eta$) correlations at small azimuthal difference ($\Delta\phi$) are observed in high multiplicity p+p and p+Pb collisions at the LHC. Subtraction of the di-hadron correlation in low-multiplicity p+Pb collisions from high-multiplicity ones reveals a back-to-back double ridge structure ($\Delta\phi\approx 0$ and $\pi$). A similar double ridge is observed in...
Zhongbo Kang
(L)
19/05/2014, 17:50
Initial State Physics
Contributed Talk
The quest for experimental signatures of small-x gluon saturation has been one of the major goals in p+A (d+A) programs at RHIC and LHC. Experimental measurements of single particle and two-particle correlations in the forward direction have revealed novel nuclear suppression patterns, which might help pinpoint the small-x gluon dynamics. At the moment there are two formalisms which can both...
Dr
Hannu Paukkunen
(University of Jyväskylä)
19/05/2014, 18:10
Initial State Physics
Contributed Talk
We present a perturbative QCD analysis concerning the production of high-pT
dijets in p+Pb collisions at the LHC. The next-to-leading order corrections, scale
variations and free-proton PDF uncertainties are found to have only a relatively
small influence on the normalized dijet rapidity distributions. Interestingly, however, these novel observables prove to retain substantial sensitivity...
