DPF 2009

Session

Heavy Ions III

31 Jul 2009, 14:00

Wayne State University

417. Evolution of the ridge structure in RHIC heavy ion collisions

Mr Chanaka De Silva (Wayne State University)

31/07/2009, 14:00

Heavy Ion Physics/Hot and Dense QCD

Two particle correlation measurements at RHIC have shown an extended near side delta eta correlation in heavy-ion collisions relative to p+p for both momentum triggered and untriggered analyses. This phenomenon is also known as the "ridge". An investigation into the momentum dependence of two particle correlations is presented for Cu+Cu 200 GeV collisions from the STAR experiment. We extract...

50. Soft Contribution to the Hard Ridge

Mr George Moschelli (Wayne State University)

31/07/2009, 14:25

Heavy Ion Physics/Hot and Dense QCD

Jet correlation measurements at RHIC show a striking increase in the yield of associated particles in a narrow range in relative azimuthal angle near $\phi\approx 0$. This region of enhanced particle production is called a ridge because it extends over a broad range in relative pseudorapidity. Interestingly, a similar `soft' ridge of enhanced production has been reported for two-particle...

250. Bridging the soft and the hard at RHIC: collective flow, jet quenching and medium response.

Dr Jiangyong Jia (Brookhaven National Laboratory (BNL) and Stony Brook University)

31/07/2009, 14:50

Heavy Ion Physics/Hot and Dense QCD

Measurements from RHIC at intermediate $p_T$ of 2-6 GeV/c revealed many features in various single particle and two particle correlation observables. These measurements not only suggest the leading roles of collective flow and jets in this $p_T$ region, but also establish a strong and sophisticated coupling between the two. Experimental results are discussed in the hope to elucidate the...

177. A theory of jet shapes and cross sections in hadronic and nuclear collisions

Dr Ivan Vitev (LANL)

31/07/2009, 15:25

Heavy Ion Physics/Hot and Dense QCD

For jets, with great power comes great opportunity. The unprecedented center of mass energies available at the LHC open new windows on the QGP: we demonstrate that jet shape and jet cross section measurements become feasible as a new, differential and accurate test of the underlying QCD theory. We present a first step in understanding these shapes and cross sections in heavy ion reactions. Our...

32. Full Jet Reconstruction In Heavy Ion Collisions: Prospects and Perils

Dr Sevil Salur (LBL)

31/07/2009, 16:30

Heavy Ion Physics/Hot and Dense QCD

Full jet reconstruction has traditionally been thought to be difficult in heavy ion events, due to large multiplicity backgrounds. The search for new physics in high luminosity p+p collisions at the LHC similarly requires the precise measurement of jets over large backgrounds due to pile up, and has motivated the development a new generation of jet reconstruction algorithms which are also...

326. Direct jet reconstruction in p + p and Cu + Cu at PHENIX

Yue Shi Lai (Columbia University-Unknown-Unknown)

31/07/2009, 17:00

Heavy Ion Physics/Hot and Dense QCD

The Relativistic Heavy Ion Collider uses the collision of heavy nuclei to create a strongly interacting, partonic medium, while the collision of $p + p$ provides a baseline measurement to determine the medium modification effect. Direct jet reconstruction applied to these collision systems offers a crucial constraint on the mechanism for in-medium parton energy loss and jet-medium...

455. Modification of high p_{T} hadro-chemistry in Au+Au collisions relative to p+p

Dr Anthony Timmins (Wayne State University)

31/07/2009, 17:30

Heavy Ion Physics/Hot and Dense QCD

We present high p_{T} pion, proton, kaon, and rho spectra measured with the STAR experiment in p+p and Au+Au collisions at 200 GeV. We find the kaon/pion ratio to be enhanced in Au+Au 200 GeV collisions relative to p+p 200 GeV collisions at p_T 6 GeV/c. The enhancement persists until p_{T} ~ 11 GeV/c for central Au+Au 200 GeV collisions. We also show R_{AA} measured at the ...

158. Hadro-Chemistry with High-PT Particles in Nuclear Collisions

Prof. Rainer Fries (Texas A&M University & RBRC)

31/07/2009, 18:00

Heavy Ion Physics/Hot and Dense QCD

I will discuss some basic ideas about changes in the chemical composition of QCD jets traversing nuclear matter. I will focus in particular on "conversions" of jets in quark gluon plasma and their effect on spectra and azimuthal asymmetries of high-PT hadrons and photons. I discuss possible signatures at RHIC and the LHC heavy ion program and review recent experimental results.