Hard Probes 2012

Session

Parallel IIIB: Jet quenching and energy loss

29 May 2012, 14:15

Cagliari - Italy

12. Out of Medium Fragmentation from Long-Lived Jet Showers

Jorge Casalderrey-Solana (U. de Barcelona)

29/05/2012, 14:15

Oral presentation

We study the time structure of vacuum jet evolution via a simple uncertainty principle estimate in the kinematic range explored by current heavy ion collisions at the LHC. We observe that a large fraction of the partonic splittings occur at large times, of the order of several fm. We compare the time distribution of vacuum splittings with the distribution of path lengths traversed by jets in a...

62. Coherence and broadening effects in medium induced gluon radiation

Mauricio Martinez Guerrero (Universidade de Santiago de Compostela)

29/05/2012, 14:35

Oral presentation

Radiative interferences in the multi-parton shower is the building block of QCD jet physics in vacuum. The presence of a hot medium made of quarks and gluons is expected to alter this interference pattern. To study such effects, we derive the gluon emission spectrum off an "asymptotic quark" traversing a hot and dense QCD medium at first order in the medium density. The resulting induced...

64. Transverse Momentum Broadening in Weakly Coupled Quark-Gluon Plasma

Mindaugas Lekaveckas (MIT)

29/05/2012, 14:55

Oral presentation

We calculate P(k_perp), the probability distribution for an energetic parton propagating for a distance L through a medium to pick up transverse momentum k_perp, for a medium consisting of weakly coupled quark-gluon plasma. We use full or HTL self-energies in appropriate regimes, resumming each in order to find the leading large-L behavior. We estimate the jet quenching parameter and compare...

53. Calculating the jet quenching parameter $\hat{q}$ in lattice gauge theory

Abhijit Majumder (Wayne State University)

29/05/2012, 15:15

Oral presentation

We present a framework where first principles calculations of jet modication may be carried out in a non-perturbative thermal environment. As an example of this approach, we compute the leading order contribution to the transverse momentum broadening of a high energy (near on-shell) quark in a thermal medium. This involves a factorization of a non-perturbative operator product from the...

27. The role of jet collimation in jet energy loss

Jose Guilherme Milhano (CENTRA-IST (Lisbon) and CERN-PH-TH)

29/05/2012, 15:35

Oral presentation

The observation of a significant enhancement of the dijet asymmetry in PbPb collisions as compared to the pp reference case, compounded with the absence of modication of the azimuthal dijet distribution, led us to highlight the importance of medium induced transverse transport of soft quanta as a source of jet energy loss. Here, we extend our analysis and explore the consequences of 'jet...