Volume 60, Issue 4
April 2003, pages 575-873
pp 575-576 April 2003
pp 577-592 April 2003
The field of relativistic heavy-ion physics is reviewed with emphasis on new results and highlights from the first run of the relativistic heavy-ion collider at BNL and the 15 year research programme at the super proton synchrotron (SPS) at CERN and the AGS at BNL.
pp 593-612 April 2003
The current status of quark gluon plasma theory is reviewed. Special emphasis is placed on QGP signatures, the interpretation of current data and what to expect from RHIC in the near future.
pp 613-625 April 2003
Results from the photon multiplicity measurements using a fine granularity pre-shower photon multiplicity detector (PMD) at CERN SPS are discussed. These include study of pseudorapidity distributions of photons, scaling of photon multiplicity with number of participating nucléons, centrality dependence of 〈pT〉 of photons, event-by-event fluctuations in photon multiplicity and localised charged-neutral fluctuations. Basic features of the PMD to be used in STAR experiment at RHIC and in ALICE experiment at LHC are also discussed.
pp 627-638 April 2003
An overview of the latest results from the STAR experiment at RHIC is presented. Preliminary measurements of π,K,p,Λ and Ξ, plus their respective anti-particles atpt < 2 GeV/c, where the majority of particle production occurs, allow us to probe the soft processes whilst the harder perturbative regime can be accessed by studying particle spectra and yields at higher momenta.
pp 639-650 April 2003
A Drees K Adcox S S Adler N N Ajitanand Y Akiba J Alexander L Aphecetche Y Arai S H Aronson R Averbeck T C Awes K N Barish P D Barnes J Barrette B Bassalleck S Bathe V Baublis A Bazilevsky S Belikov F G Bellaiche S T Belyaev M J Bennett Y Berdnikov S Botelho M L Brooks D S Brown N Bruner D Bucher H Buesching V Bumazhnov G Bunce J Burward-Hoy S Butsyk T A Carey P Chand J Chang W C Chang L L Chavez S Chernichenko C Y Chi J Chiba M Chiu R K Choudhury T Christ T Chujo M S Chung P Chung V Cianciolo B A Cole D G D’Enterria G David H Delagrange A Denisov A Deshpande E J Desmond O Dietzsch B V Dinesh A Drees A Durum D Dutta K Ebisu Y V Efremenko K El Chenawi A Enokizono H En’yo S Esumi A D Frawley S -Y Fung S Garpman T K Ghosh A Glenn A L Godoi Y Goto S V Greene M Grosse Perdekamp S K Gupta W Guryn H-Å Gustafsson T Hachiya J S Haggerty H Hamagaki A G Hansen H Hara E P Hartouni R Hayano N Hayashi X He T K Hemmick J M Heuser M Hibino J C Hill D S Ho K Homma B Hong A Hoover T Ichihara K Imai M S Ippolitov M Ishihara B V Jacak W Y Jang J Jia B M Johnson S C Johnson K S Joo S Kametani J H Kang M Kann S S Kapoor S Kelly B Khachaturov A Khanzadeev J Kikuchi D J Kim H J Kim S Y Kim Y G Kim W W Kinnison E Kistenev A Kiyomichi C Klein-Boesing S Klinksiek L Kochenda V Kochetkov D Koehler T Kohama D Kotchetkov A Kozlov P J Kroon K Kurita M J Kweon Y Kwon G S Kyle R Lacey J G Lajoie J Lauret A Lebedev D M Lee M J Leitch X H Li Z Li D J Lim M X Liu X Liu Z Liu C F Maguire J Mahon Y I Makdisi V I Manko Y Mao S K Mark S Markacs G Martinez M D Marx A Masaike F Matathias T Matsumoto P L McGaughey E Melnikov M Merschmeyer F Messer M Messer Y Miake T E Miller A Milov S Mioduszewski R E Mischke G C Mishra J T Mitchell A K Mohanty D P Morrison J M Moss F Mühlbacher M Muniruzzaman J Murata S Nagamiya Y Nagasaka J L Nagle Y Nakada B K Nandi J Newby L Nikkinen P Nilsson S Nishimura A S Nyanin J Nystrand E O’Brien C A Ogilvie H Ohnishi I D Ojha M Ono V Onuchin A Oskarsson L Österman I Otterlund K Oyama L Paffrath A P T Palounek V S Pantuev V Papavassiliou S F Pate T Peitzmann A N Petridis C Pinkenburg R P Pisani P Pitukhin F Plasil M Pollack K Pope M L Purschke I Ravinovich K F Read K Reygers V Riabov Y Riabov M Rosati A A Rose S S Ryu N Saito A Sakaguchi T Sakaguchi H Sako T Sakuma V Samsonov T C Sangster R Santo H D Sato S Sato S Sawada B R Schlei Y Schutz V Semenov R Seto T K Shea I Shein T -A Shibata K Shigaki T Shiina Y H Shin I G Sibiriak D Silvermyr K S Sim J Simon-Gillo C P Singh V Singh M Sivertz A Soldatov R A Soltz S Sorensen P W Stankus N Starinsky P Steinberg E Stenlund A Ster S P Stoll M Sugioka T Sugitate J P Sullivan Y Sumi Z Sun M Suzuki E M Takagui A Taketani M Tamai K H Tanaka Y Tanaka E Taniguchi M J Tannenbaum J Thomas J H Thomas T L Thomas W Tian J Tojo H Torii R S Towell I Tserruya H Tsuruoka A A Tsvetkov S K Tuli H Tydesjö N Tyurin T Ushiroda H W van Hecke C Velissaris J Velkovska M Velkovsky A A Vinogradov M A Volkov A Vorobyov E Vznuzdaev H Wang Y Watanabe S N White C Witzig F K Wohn C L Woody W Xie K Yagi S Yokkaichi G R Young I E Yushmanov W A Zajc Z Zhang S Zhou
pp 651-661 April 2003
A review on experimental results for direct photon production in heavy ion reactions is given. A brief survey of early direct photon limits from SPS experiments is presented. The first measurement of direct photons in heavy ion reactions from the WA98 collaboration is discussed and compared to theoretical calculations. An outlook on the perspective of photon measurements at RHIC is given.
pp 663-674 April 2003
The productions of real photons from quark gluon plasma and hot hadronic matter formed after the nucleus-nucleus collisions at ultra-relativistic energies are discussed. The effects of the spectral shift of the hadrons at finite temperature on the production of photons are investigated. On the basis of the present analysis it is shown that the photon spectra measured by WA98 collaboration in Pb + Pb collisions at CERN SPS energies can be explained by both QGP as well as hadronic initial states if the spectral shift of hadrons at finite temperature is taken into account. Several other works on the analysis of WA98 photon data have also been briefly discussed.
pp 675-686 April 2003
The current status of our understanding of dilepton production in ultra-relativistic heavyion collisions is discussed with special emphasis on signals from the (approach towards) chirally restored and deconfined phases. In particular, recent results of the CERN-SPS low-energy runs are compared to model predictions and interpreted. Prospects for RHIC experiments are given.
pp 687-696 April 2003
The talk summarizes some new results of lattice investigations of QCD at finite temperature. The topics discussed cover the flavor dependence of the critical temperature and the equation-of-state as well as hadronic correlation functions.
pp 697-709 April 2003
We review recent work on the phase structure of QCD at very high baryon density. We introduce the phenomenon of color superconductivity and discuss the use of weak coupling methods. We study the phase structure as a function of the number of flavors and their masses. We also introduce effective theories that describe low energy excitations at high baryon density. Finally, we comment on the possibility of kaon condensation at very large baryon density.
pp 711-723 April 2003
Based on general arguments, the in-medium quark propagator in a quark-gluon plasma leads to a quark dispersion relation consisting of two branches, of which one exhibits a minimum at some finite momentum. This results in a vanishing group velocity for collective quark modes. Important quantities such as the production rate of low mass lepton pairs and mesonic correlators depend inversely on this group velocity. Therefore these quantities, which follow from self energy diagrams containing a quark loop, are strongly affected by van Hove singularities (peaks and gaps). If these sharp structures could be observed in relativistic heavy-ion collisions it would reveal the physical picture of the quark-gluon plasma (QGP) as a gas of quasiparticles.
pp 725-737 April 2003
Peter Seyboth S V Afanasiev T Anticic D Barna J Bartke R A Barton L Betev H Bialkowska A Billmeier C Blume C O Blyth B Boimska M Botje J Bracinik R Bramm R Brun P Bunci V Cerny O Chvala J G Cramer P Csato P Dinkelaker V Eckardt P Filip H G Fischer Z Fodor P Foka P Freund V Friese J Gal M Gaździcki G Georgopoulos E Gladysz S Hegyi C Hohne P G Jones K Kadija A Karev V I Kolesnikov T Kollegger M Kowalski I Kraus M Kreps M van Leeuwen P Levai A I Malakhov C Markert B WMayes G L Melkumov A Mischke J Molnar J M Nelson G Palla A D Panagiotou K Perl A Petridis M Pikna L Pinsky F Puhlhofer J G Reid R Renfordt W Retyk C Roland G Roland A Rybicki A Sandoval H Sann N Schmitz Peter Seyboth F Sikler B Sitar E Skrzypczak G T A Squier R Stock H Strobele T Susa I Szentpetery J Sziklai T A Trainor D Varga M Vassiliou G I Veres G Vesztergombi D Vranic S Wenig A Wetzler I KYoo J Zaranek J Zimanyi
Experiment NA49 at the CERN SPS uses a large acceptance detector for a systematic study of particle yields and correlations in nucleus-nucleus, nucleon-nucleus and nucleon-nucleon collisions. Preliminary results for Pb+Pb collisions at 40, 80 and 158 A⋅GeV beam energy shown and compared to measurements at lower and higher energies.
pp 739-752 April 2003
Measurements of azimuthal distribution of inclusive photons using the fine granularity pre-shower photon multiplicity detector (PMD) at CERN SPS are used to obtain anisotropy in the azimuthal distributions. These results are used to estimate the anisotropy in the neutral pion distributions. The results are compared with results of charged particle data, both for first order and second order anisotropy. Assuming the same anisotropy for charged and neutral pions, the anisotropy in photons is estimated and compared with the measured anisotropy. The effect of neutral pion decay on the correlation between the first order and the second order event plane is also discussed. Data from PMD can also be used to estimate the reaction plane for studying any anisotropy in particle emission characteristics in the ALICE experiment at the large hadron collider (LHC). In particular, we show that using the event plane from the PMD, it will be possible to measure the anisotropy inJ/Ψ absorption (if any) in the ALICE experiment.
pp 753-763 April 2003
First observations of elliptic flow in Au-Au collisions at RHIC have been interpreted as evidence that the colliding system reaches thermal equilibrium. We discuss some of the arguments leading to this conclusion and show that a more accurate analysis is needed, which the standard flow analysis may not provide. We then present a new method of flow analysis, based on a systematic study of multiparticle azimuthal correlations. This method allows one to test quantitatively the collective behaviour of the interacting system. It has recently been applied by the STAR Collaboration at RHIC.
pp 765-786 April 2003
In this talk, I present what I believe we have learned from the recent RHIC heavy ion experiments. The goal of these experiments is to make and study matter at very high energy densities, greater than an order of magnitude larger than that of nuclear matter. Have we made such matter? What have we learned about the properties of this matter? What do we hope and expect to learn in the future?
pp 787-794 April 2003
Recent work on chemical equilibrium in heavy-ion collisions is reviewed. The energy dependence of thermal parameters is discussed. The centrality dependence of thermal parameters at SPS energies is presented.
pp 795-816 April 2003
This review of low-pT proton-proton physics at low luminosity at the large hadron collider (LHC) should cover all LHC experiments, but in practice, is mainly related to ALICE, for reasons which will be explained. However, the relevance to other LHC experiments is clear, as low-pT. phenomena represent an important component of the background to their high-pT. phenomena which needs to be calibrated. The ALICE collaboration will study proton-proton collisions as part of their heavy-ion programme, where most signals are relative to the proton-proton system. In addition, the ALICE detector’s unique acceptance at low pT as well as its unique particle identification capability will make it possible to carry out a program of genuine proton-proton physics complementary to those of other LHC experiments.
pp 817-828 April 2003
Paula bordalo M C Abreu B Alessandro C Alexa R Arnaldi M Atayan C Baglin A Baldit M Bedjidian S Beolé V Boldea Paula Bordalo S R Borenstein C Borges A Bussiére L Capelli C Castagner J Castor B Chaurand B Cheynis E Chiavassa C Cicaló T Claudino M P Comets N Constans S Constantinescu P Cortese J Cruz A De Falco G Dellacasa N De Marco A De vaux S Dita O Drapier B Espagnon J Fargeix P Force M Gallio Y K Gavrilov C Gerschel P Giubellino M B Golubeva M Gonin A A Grigorian J Y Grossiord F FGuber A Guichard H Gulkanyan R Hakobyan R Haroutunian M Idzik D Jouan T L Karavitcheva L Kluberg A B Kurepin Y Le Bornec C Lourenço P Macciotta M Mac Cormick A Marzari-Chiesa M Masera A Masoni M Monteno A Musso P Petiau A Piccotti J R Pizzi W Prado Da Silva F Prino G Puddu C Quintans S Ramos L Ramello P Rato Mendes L Riccati A Romana P Saturnini H Santos E Scalas E Scomparin S Serci R Shahoyan F Sigaudo S Silva M Sitta P Sonderegger X Tarrago N S Topilskaya G L Usai E Vercellin L Villatte N Willis
TheJ/Ψ production in 158 A GeV Pb-Pb interactions is studied, in the dimuon decay channel, as a function of centrality, as measured with the electromagnetic or, alternatively, with the very forward hadronic calorimeters. After a first sharp variation at mid-centrality, both patterns continue to fall down and exhibit a curvature change at high centrality values. This trend excludes any conventional hadronic model and finds a natural explanation in a deconfined quark-gluon phase scenario.
pp 829-840 April 2003
I discuss quarkonium suppression in equilibrated strongly interacting matter. After a brief review of basic features of quarkonium production I discuss the application of recent lattice data on the heavy quark potential to the problem of quarkonium dissociation as well as the problem of direct lattice determination of quarkonium properties in finite temperature lattice QCD.
pp 841-850 April 2003
For more than 25 yearsJΨ production has helped to sharpen our understanding of QCD. In proton induced reaction some observations are rather well understood while others are still unclear. The current status of the theory ofJΨ production will be sketched, paying special attention to the issues of formation time andJΨ re-interaction in a nuclear medium.
pp 851-863 April 2003
The large hadron collider (LHC) under construction at CERN will deliver ion beams up to centre of mass energies of the order of 5.5 TeV per nucleon, in case of lead. If compared to the available facilities for the study of nucleus-nucleus collisions (SpS and RHIC), this represents a huge step forward in terms of both volume and energy density that can be attained in nuclear interactions. ALICE (a large ion collider experiment) is the only detector specifically designed for the physics of nuclear collisions at LHC, even though it can also study high cross-section processes occurring in proton-proton collisions. The main goal of the experiment is to observe and study the phase transition from hadronic matter to deconfined partonic matter (quark gluon plasma —QGP). ALICE is conceived as a general-purpose detector and will address most of the phenomena related to the QGP formation at LHC energies: for this purpose, a large fraction of the hadrons, leptons and photons produced in each interaction will be measured and identified.
pp 865-873 April 2003
Volume 93 | Issue 5
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