DOCSLIB.ORG

QUARK DECONFINEMENT and HIGH Energf I9 NUCLEAR COLLISIONS

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
QUARK DECONFINEMENT and HIGH Energf I9 NUCLEAR COLLISIONS BNL—38530 BROOKHAVIN NATIONAL LABORATORY DE87 001374 July 1986 BNL- ' >••> QUARK DECONFINEMENT AND HIGH ENERGf I9 NUCLEAR COLLISIONS H. Satz Fakultat fur Physik Universitat Bielefeld, D-48 Bielefeld, F.R. Germany and Physics Department Brookltaven National Laboratory, Upton, NY 11973, USA ABSTRACT Statistical QCD predicts that with increasing density, strongly inter- acting matter will undergo a transition to a plasma of deconfined quarks and gluons. High energy heavy ion collisions are expected to permit exper- imental studies of this transition and of the predicted new state of matter. Talk given at the XXIII International Conference on High Energy Physics, 1C-23 July 1980, Berkeley, California, USA. This manuscript has been authored under contract number D10-ACO2-7OCIIOUU1C with the U.S. Depn.rt.- ment of Energy. Accordingly, the U.S. Government retains a non-exclusive, royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for U.S. Government purposes. DISTRIBUTION OF THIS DOCUMEKT !S UNLIMITED yfi 1. Introduction High energy hadron collisions have provided the empirical basis for strong interaction dynamics. It is our hope that high energy heavy ion collisions will do the same for strong interaction thermodynamics, that they will become the tool with which we can carry out the experimental analysis of strongly interacting matter. We recall that thermodynamics, in studying the collective behaviour of many components, may well lead to new physics, beyond the known dynamics. In solid state physics, ferromagnetism and superconductivity are just two striking examples of this. We shall see shortly that the statistical mechanics obtained with QCD as dynamical input in fact does predict new states of matter. Heavy ion experiments, starting this fall at the AGS (Brookhaven)1 and the SPS (CERN)2 will attempt to observe and study these states experimentally. Already on a phenomenological level, we may expect strongly interacting matter to undergo two phase transitions: colour deconfinement and chiral symmetry restoration. Let us therefore begin by looking at these transitions as specific cases of rather general phenomena in statistical physics. The binding potential V (r) between two charges separated by a distance r is modified by the presence of other charges. In atomic physics, we obtain the Debye-screened form V (r) exp {—r/ru), where the screening radius rj) decreases with increasing charge density. When TJJ ai rg, where rg denotes the binding radius, the system undergoes a transition from insulator to conductor, since the screening now liberates the valence electron. Simi- larly, we expect for strongly interacting matter a transition from colour insulator (hadronic matter) to colour conductor (quark-gluon plasma), once the density of colour charges is sufficient to make rjy^rjj, where rjj is the hadron radius.3 At sufficiently high density, the long range, confining part of the potential thus becomes screened and we expect quark deconfinement. A conduction electron in a metal generally has a different effective mass than that of an electron in vacuum or bound in an isolated hydrogen atom. This shift in mass is a collective effect due to the lattice and the other electrons in the conductor. Similarly, we expect that the quarks inside a hadron will have a different effective mass than they have in a plasma at high density. For the latter, asymptotic freedom leads eventually to a vanishing quark mass, while inside hadrons we have constituent quarks of mass m|ff a 300 MeV. A theory with massless quarks is chirally symmetric. At low density, this symmetry must thus be spontaneously broken; at high density, when m|ff —> 0, chiral symmetry is restored. We thus expect two types of transition in strongly interacting matter: quark decon- finement as the result of colour charge screening at high density, and chiral symmetry restoration as the result of a shift in the quark mass when the system changes from colour insulator to conductor. Are the two phenomena connected, and what are the transition parameters? For this, we now turn to statistical QCD. 2. Statistical QCD The basis for strong interaction dynamics is the QCD Lagrangian a t = -\{d»A v -dvA%- gfe 4 Aiy -Y^$f(if tf where A and ip are the gluon and quark fields, respectively; the corresponding colour indices take on the values a, b, c = 1, • • •, 8 and a, (3 = 1,2,3. We shall in general consider only two quark flavours (u, d); these we take as massless. Strong interaction thermodynamics is then based on the partition function Z (T, /x, V) = Tr{exp [- [H - n N) /T]}, (2) where H (£,) is the Hamiltonian, N the net overall baryon number, and (j, the associated baryonic chemical potential. With Eq. (1) and (2), statistical QCD is in principle completely defined. Given Z, we obtain by differentiation all thermodynamic observables of interest, such as e=(T*/V)(dlnZ/dT)llfT>v (3) for the energy density, or nB = {T/V) (dinZ/dn)Ty (4) for the baryon number density. To evaluate Z, however, we need a regularizing, non-perturbative method of treating the relativistic quantum field problem implied by Eq. (1). Since we want to study critical behaviour, a perturbative approach as used in QED is not adequate. So far, the only scheme which allows a solution of this problem is the lattice formulation proposed by K. Wilson.4 It leads to a partition function similar in form to those encountered in the statis- tical mechanics of spin systems and can therefore be solved by Monte Carlo simulation on sufficiently large computers.5 We shall here go immediately to the results obtained through this approach; for a recent survey giving more details of formulation and evaluation, see Ref. 6. The energy density of an ideal gas of massless quarks and gluons, for colour SU (3) and two quark flavours, is given by the generalized Stefan-Boltzmann form (5) An ideal gas of massless pions leads to (6) The energy density of strongly interacting matter, as obtained by computer simulation of the QCD expression (3) with Eq. (1) and (2), is shown in fig. 1. It is displayed there as a function of the inverse coupling 6/g2, which is connected to the physical temperature through the renormalization group relation lnT ~ 6/g2. At low temperature, the energy density is seen to be close to the pion gas value (6); at a point corresponding to about Tc ~ 200MeV, it changes abruptly and starts to approach the ideal plasma value (5). To see if this transition indeed corresponds to deconfinement, we need an order pa- rameter indicating which phase the system is in. It is given by the average thermal Wilson loop L,7'8 which is related to the free energy F of an isolated quark, L~exp{-F/T}. (7) In the confinement regime, there can be no free quarks and F becomes infinite; once colour screening sets in, it is possible to separate a qq pair, and hence F becomes finite. Confinement is thus indicated by Z ~ 0, and when deconfinement occurs, L jumps abruptly to much larger values. In fig. 2 we see that this is indeed the behaviour which follows from statistical QCD, and the transition temperatures from L and e agree, as expected. Next, we want to look at chiral symmetry restoration. Here the order parameter is (•4>ip), which provides a measure of the effective quark mass. Hence for (ipip) a 0, we have chiral symmetry, while for (iptp) >• 0 it is spontaneously broken. In fig. 3 we compare the order parameters for deconfinement and chiral symmetry restoration; it is seen that the two phenomena occur at the same transition temperature. Let us note that the results of statistical QCD, which we have just summarized, have been obtained by a number of different groups using quite different techniques to accom- modate quarks in the lattice formulation (for a compilation, see Ref. 6). They all find very similar behaviour, both qualitatively and quantitatively. We can therefore conclude that statistical QCD predicts for vanishing baryon number density a meson gas at low temperatures, colour deconfinement and chiral symmetry restoration at Tc OL 200 MeV, and for higher temperatures, a plasma of deconfined, massless quarks and gluons. The energy density necessary to attain this plasma is about 2.5GeV/fm3. What happens when we now pass from "mesonic" matter with vanishing baryon num- ber density to "baryonic" matter, for which fi ^ 0 in Eq. (2)? In this case the Monte Carlo evaluation encounters technical difficulties (complex quark determinant), which are presently being addressed by various groups; they are not yet resolved, however. There- fore, only approximative results9 are available so far; nevertheless, they give us some first indications of what to expect. In fig. 4 we show the temperature dependence of the deconfinement order parameter L for different values of the baryonic chemical potential (i. As fj. and hence the baryon number density increase, the transition point is shifted to lower temperatures. Such an effect is expected: deconfinement can be caused either by heating or by compression, and if compressed, the system requires less heating to become critical. The use of pressure — here in the form of an increased baryon number density — in inducing deconfinement is seen quite clearly in fig. 5, where the order parameter shows a ^-dependence very similar to the T-dependence of fig. 2. The present, approximative evaluation goes up to /j, a 800 MeV; so far, deconfinement and chiral symmetry restoration continue to coincide, as seen in fig. 6. Whether this will hold down to T = 0 remains to be seen; in principle, a three phase structure is not yet excluded.
Load more

Recommended publications
  • Surprises from the Search for Quark-Gluon Plasma?* When Was Quark-Gluon Plasma Seen?
    Surprises from the search for quark-gluon plasma?* When was quark-gluon plasma seen? Richard M. Weiner Laboratoire de Physique Théorique, Univ. Paris-Sud, Orsay and Physics Department, University of Marburg The historical context of the recent results from high energy heavy ion reactions devoted to the search of quark-gluon plasma (QGP) is reviewed, with emphasis on the surprises encountered. The evidence for QGP from heavy ion reactions is compared with that available from particle reactions. Keywords: Quark-Gluon plasma in particle and nuclear reactions, hydrodynamics, equation of state, confinement, superfluidity. 1. Evidence for QGP in the Pre-SPS Era Particle Physics 1.1 The mystery of the large number of degrees of freedom 1.2 The equation of state 1.2.1 Energy dependence of the multiplicity 1.2.2 Single inclusive distributions Rapidity and transverse momentum distributions Large transverse momenta 1.2.3 Multiplicity distributions 1.3 Global equilibrium: the universality of the hadronization process 1.3.1 Inclusive distributions 1.3.2 Particle ratios -------------------------------------------------------------------------------------- *) Invited Review 1 Heavy ion reactions A dependence of multiplicity Traces of QGP in low energy heavy ion reactions? 2. Evidence for QGP in the SPS-RHIC Era 2.1 Implications of observations at SPS for RHIC 2.1.1 Role of the Equation of State in the solutions of the equations of hydrodynamics 2.1.2 Longitudinal versus transverse expansion 2.1.3 Role of resonances in Bose-Einstein interferometry; the Rout/Rside ratio 2.2 Surprises from RHIC? 2.2.1 HBT puzzle? 2.2.2 Strongly interacting quark-gluon plasma? Superfluidity and chiral symmetry Confinement and asymptotic freedom Outlook * * * In February 2000 spokespersons from the experiments on CERN’s Heavy Ion programme presented “compelling evidence for the existence of a new state of matter in which quarks, instead of being bound up into more complex particles such as protons and neutrons, are liberated to roam freely…”1.
    [Show full text]
  • Deconfinement and Chiral Transition in Ads/QCD Wall Models
    EPJ Web of Conferences 137, 03006 (2017) DOI: 10.1051/ epjconf/201713703006 XIIth Quark Confinement & the Hadron Spectrum Deconfinement and chiral transition in AdS/QCD wall models supplemented with a magnetic field David Dudal1;2;a, Diego R. Granado3;b, and Thomas G. Mertens4;2;c 1KU Leuven Campus Kortrijk - KULAK, Department of Physics, Etienne Sabbelaan 51 bus 7800, 8500 Kor- trijk, Belgium 2Ghent University, Department of Physics and Astronomy, Krijgslaan 281-S9, 9000 Gent, Belgium 3Departamento de Física, Universidade Federal Rural do Rio de Janeiro, BR 465-07, 23890-971, Seropédica, RJ, Brasil 4Joseph Henry Laboratories, Princeton University, Princeton, NJ 08544, USA Abstract. We discuss the phenomenon of (inverse) magnetic catalysis for both the de- confinement and chiral transition. We discriminate between the hard and soft wall model, which we suitably generalize to include a magnetic field. Our findings show a critical de- confinement temperature going down, in contrast with the chiral restoration temperature growing with increasing magnetic field. This is at odds with contemporary lattice data, so the quest for a holographic QCD model capable of capturing inverse magnetic catalysis in the chiral sector remains open. 1 Introduction The ongoing heavy ion collision programs (ALICE or RHIC) provide a fertile testing ground for novel experimental, phenomenological and theoretical features of strongly coupled QCD. During the early stages after the collision, a sufficiently hot heat bath is created that leads to the creation of a quark- gluon plasma, an exotic state of deconfined QCD matter. In units of the fundamental QCD scale, ΛQCD, the transition temperature Tdecon f ∼ ΛQCD, so the relevant physics is still strongly coupled.
    [Show full text]
  • Excited Hadron States and the Deconfinement Transition
    Excited Hadron States and the Deconfinement Transition Concluding Discussion Berndt Müller (Duke University) Workshop*) JLab - February 23-25, 2011 Friday, February 25, 2011 If we would hold a follow-up workshop in 2 years from now, which questions would we like to be answered? 2 Friday, February 25, 2011 Which QCD model describes the hadron (meson, baryon) spectrum best? E.g.: Constituent quark model MIT bag model Flux-tube model Holographic dual models Large Nc expansion Is there a “constituent gluon” model? If yes, how do we understand the large gluon mass? Scale breaking by the trace anomaly? Additional spontaneous scale invariance breaking? Is the constituent gluon a flux tube excitation? 3 Friday, February 25, 2011 What is the relation between the deconfinement transition and the chiral transition? Is it a well defined question? Are they at the “same” temperature? Do they drive each other? Where (at what T) and why does the hadron resonance gas model fail? Do unknown hadron states (hybrids, tetraquarks, glueballs) contribute significantly in the range of validity? If yes, which ones? 4 Friday, February 25, 2011 What are the requirements for a valid description of the hadronic break-up of the quark-gluon plasma? How must viscous hydrodynamics be matched to a kinetic description of the hadron gas? What are the minimal matching conditions? In which temperature range can the matching be performed? What are the most sensitive experimental tests? Where does the hot glue in the quark-gluon plasma go? Does it fragment into quark pairs? Does it initially end up in gluonic excitations? Is it possible to measure the average amount of excited glue in hadrons for a given mass or temperature on the lattice? 5 Friday, February 25, 2011 Can finite temperature lattice calculations determine average aspects of the hadron spectrum? Analogy with the Monte-Carlo shell model of Koonin, Ormand, Dean, Langanke, et al, who used MC methods to obtain level densities and Gamov-Teller strengths in the shell model for complex nuclei (e.g.
    [Show full text]
  • Nora Brambilla Quark Confinement and the Hadron Spectrum
    Quark Confinement and the Hadron Spectrum XII Nora Brambilla Nora Brambilla Thessaloniki, 28 TU MUNICH August-4 September TU Munich 2016 4el Much of the way in which we develop science Aristotele’s apprehension of reality Aristotele’ school TIMES changed …… Conf12 venue but other things resisted the time the beauty of the place but other things resisted the time the temper, the determination and the ambition of the “locals” Modern Heros that organised 10 days of conference(s) with 400 participants, hundreds of talks, 7 sessions running in parallel , a social event each night and…. almost NO FUNDS ! and what allowed to surpass any difficulty was.. to have as Chair a true descendant of Cleopatra with the same inherited personality We can say that the Quark Confinement Conference shares some of the important Macedonian footprints • “Many different nations, cultures, languages.... “Macedoin” now means “a mix” We have the ambition to bring together all the people dealing with strong interactions from one perspective or the other Scientific Sessions of the conference Section A: Vacuum Structure and Confinement Mechanisms of quark confinement (vortices, monopoles, calorons...) and the structure of the vacuum in non-Abelian gauge theories. Chiral symmetry breaking, and the Dirac spectrum in the low-momentum region. Studies of ghost and gluon propagators. Confining strings and flux tubes, their effective actions. Renormalons and power corrections. Interface between perturbative and non-perturbative physics. Conveners: D. Antonov (Heidelberg), M. Faber (TU Vienna), J. Greensite (San Francisco State U) Focus Subsection: Emergent gauge fields and chiral fermions Chiral Fermions and anomalous hydrodynamic effects in condensed matter systems, quantum simulators of QCD, topological phenomena in condensed matter systems.
    [Show full text]
  • Arxiv:2011.01466V2 [Hep-Lat] 28 Dec 2020
    Deconfinement and Hadron Resonance Gas for Heavy ∗ Quarks Peter Petreczky Physics Deparment, Brookhaven National Laboratory, Upton, NY 11973, USA I discuss the deconfinement transition in 2+1 flavor QCD in terms of Polyakov loops as well as the hadron resonance gas for hadrons containing static quarks and charm quarks. PACS numbers: 12.38.Gc,12.38.Mh,25.75.Nq 1. Introduction Heavy quarks and infinitely heavy (static) quarks play an important role when discussing deconfinement transition in strongly interacting matter at high temperatures. The early works on deconfinement considered the free energy of static quark Q as well as the free energy of static quark antiquark (QQ¯) pair [1, 2, 3] and the lattice calculations of these quantities was a focus of many works, see Ref. [4] for a historic review. Deconfinement is closely related to color screening. The production rate of quarkonia, bound states of a heavy quark and anti-quark, was suggested as a probe of deconfinement in heavy ion collisions [5]. The basic idea behind this proposal was that the color screening in the deconfined medium effects the binding of heavy quarks (see also Ref. [6] for a review). Recent lattice QCD studies, however, mostly focus on the chiral aspects of the transition at high temperature, see e.g. Refs. [7, 8] for recent reviews. In this contribution I will discuss the deconfinement in 2+1 flavor QCD with (almost) physical quark masses in arXiv:2011.01466v2 [hep-lat] 28 Dec 2020 terms of Polyakov loops in different renormalization schemes. The Hadron Resonance Gas (HRG) model has been used to understand the thermodynamics below the cross-over temperature for many years [9, 10, 11, 12, 12, 13, 14, 15, 16].
    [Show full text]
  • Gravitating Bubbles of Gluon Plasma Above Deconfinement Temperature
    S S symmetry Article Gravitating Bubbles of Gluon Plasma above Deconfinement Temperature Yves Brihaye 1 and Fabien Buisseret 2,3,∗ 1 Service de Physique de l’Univers, Champs et Gravitation, UMONS Research Institute for Complex Systems, Université de Mons, Place du Parc 20, 7000 Mons, Belgium; [email protected] 2 Service de Physique Nucléaire et Subnucléaire, UMONS Research Institute for Complex Systems, Université de Mons, Place du Parc 20, 7000 Mons, Belgium 3 CeREF, Chaussée de Binche 159, 7000 Mons, Belgium * Correspondence: [email protected] Received: 2 September 2020; Accepted: 8 October 2020; Published: 13 October 2020 Abstract: The equation of state of SU(3) Yang–Mills theory can be modelled by an effective Z3−symmetric potential depending on the temperature and on a complex scalar field f. Allowing f to be dynamical opens the way to the study of spatially localized classical configurations of the scalar field. We first show that spherically symmetric static Q-balls exist in the range (1 − 1.21) × Tc, Tc being the deconfinement temperature. Then we argue that Q-holes solutions, if any, are unphysical within our framework. Finally, we couple our matter Lagrangian to Einstein gravity and show that spherically symmetric static boson stars exist in the same range of temperature. The Q-ball and boson-star solutions we find can be interpreted as “bubbles” of deconfined gluonic matter; their mean radius is always smaller than 10 fm. Keywords: deconfinement; Matter-gravity coupling; Yang–Mills theory; Q-ball; boson star 1. Introduction A fascinating feature of Yang–Mills theory is the existence of a deconfinement temperature, Tc, above which free color charges (free gluons) may propagate without being confined into color singlets [1,2].
    [Show full text]
  • Hagedorn's Hadron Mass Spectrum and the Onset of Deconfinement
    Chapter 11 Hagedorn’s Hadron Mass Spectrum and the Onset of Deconfinement Marek Ga´zdzicki and Mark I. Gorenstein Abstract A brief history of the observation of the onset of deconfinement—the beginning of the creation of quark-gluon plasma in nucleus–nucleus collisions with increasing collision energy—is presented. It starts with the measurement of the hadron mass spectrum and Hagedorn’s hypothesis of the limiting temperature of hadronic matter (the Hagedorn temperature). Then the conjecture that the Hagedorn temperature is the phase transition temperature was formulated with the crucial Hagedorn participation. It was confirmed by the observation of the onset of deconfinement in lead–lead collisions at the CERN SPS energies. 11.1 Hadron Mass Spectrum and the Hagedorn Temperature A history of multi-particle production started with the discoveries of hadrons, first in cosmic-ray experiments and soon after in experiments using beams of particles produced in accelerators. Naturally, the first hadrons, discovered in collisions of cosmic-ray particles, were the lightest ones, pion, kaon and . With the rapid advent of particle accelerators new particles were uncovered almost daily. About 1,000 hadronic states are known so far. Their density in mass .m/ increases approxi- mately exponentially as predicted by Hagedorn’s Statistical Bootstrap Model [1] formulated in 1965: .m/ D const ma exp.bm/: (11.1) M. Ga´zdzicki () Goethe-University, Frankfurt, Germany Jan Kochanowski University, Kielce, Poland M.I. Gorenstein () Bogolyubov Institute for Theoretical Physics, Kiev, Ukraine Frankfurt Institute for Advanced Studies, Frankfurt, Germany © The Author(s) 2016 87 J. Rafelski (ed.), Melting Hadrons, Boiling Quarks – From Hagedorn Temperature to Ultra-Relativistic Heavy-Ion Collisions at CERN, DOI 10.1007/978-3-319-17545-4_11 88 M.
    [Show full text]
  • A Simple Introduction to Ads/CFT and Its Application to Condensed Matter Physics
    A simple introduction to AdS/CFT and its application to condensed matter physics. D-ITP Advanced Topics in Theoretical Physics Fall 2013 K. Schalm and R. Davison1 1Instituut-Lorentz for Theoretical Physics, Universiteit Leiden, P. O. Box 9506, 2300 RA Leiden, The Netherlands∗ (Dated: December 8, 2013) Abstract The anti-de Sitter/ Conformal Field theory correspondence provides a unique novel perspective on critical phenomena at second order quantum phase transitions in systems with spatial dimensions d > 1. The first half of these lectures will provide technical background to apply the so called "holographic" techniques of the correspondence. The second half discusses the application to quantum phase transitions in condensed matter: how spontaneous symmetry breaking in a quantum critical system is similar and different to the standard case, the notion of semi-local quantum liquids and their connection to non-Fermi liquids and strange metals. There are also many lecture notes available. A sample of references are: • J. Erdmenger, Introduction to gauge gravity duality, Chapters 1,2,4,5,6. • S.A. Hartnoll, Lectures on holographic methods for condensed matter physics, Class. Quant. Grav. 26, 224002 (2009). • N. Iqbal, H. Liu and M. Mezei, Lectures on holographic non-Fermi liquids and quantum phase tran- sitions. ∗Electronic address: [email protected] 1 Contents I Lecture I 1. Context and Background 4 2. Anti-de-Sitter space 5 3. Exercises 8 4. The AdS/CFT correspondence 10 4.1. CFT brush up 10 4.2. AdS/CFT 10 II Lecture II: 5. The physics of AdS/CFT Correlation functions 11 6. AdS/CFT at finite temperature: Black Holes, and the Hawking Page transition as the holographic encoding of confinement/deconfinement 14 7.
    [Show full text]
  • Strong-Interaction Matter Under Extreme Conditions from Chiral Quark Models with Nonlocal Separable Interactions
    S S symmetry Review Strong-Interaction Matter under Extreme Conditions from Chiral Quark Models with Nonlocal Separable Interactions Daniel Gómez Dumm 1,*, Juan Pablo Carlomagno 1 and Norberto N. Scoccola 2,3 1 IFLP, CONICET-Departamento de Física, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 67, 1900 La Plata, Argentina; carlomagno@fisica.unlp.edu.ar 2 Physics Department, Comisión Nacional de Energía Atómica, Av. Libertador 8250, 1429 Buenos Aires, Argentina; [email protected] 3 CONICET, Rivadavia 1917, 1033 Buenos Aires, Argentina * Correspondence: dumm@fisica.unlp.edu.ar Abstract: We review the current status of the research on effective nonlocal NJL-like chiral quark models with separable interactions, focusing on the application of this approach to the description of the properties of hadronic and quark matter under extreme conditions. The analysis includes the predictions for various hadron properties in vacuum, as well as the study of the features of deconfinement and chiral restoration phase transitions for systems at finite temperature and/or density. We also address other related subjects, such as the study of phase transitions for imaginary chemical potentials, the possible existence of inhomogeneous phase regions, the presence of color superconductivity, the effects produced by strong external magnetic fields and the application to the description of compact stellar objects. Keywords: Nonlocal Nambu-Jona-Lasinio model; finite temperature and/or density; chiral phase transition; deconfinement transition Citation: Gómez Dumm, D.; Carlomagno, J.P.; Scoccola, N.N. Strong-Interaction Matter under 1. Introduction Extreme Conditions from Chiral The detailed understanding of the behavior of strong-interaction matter under extreme Quark Models with Nonlocal conditions of temperature and/or density has attracted great attention in the past decades.
    [Show full text]
  • Advances in Quark Gluon Plasma
    Advances in Quark Gluon Plasma Gin´esMart´ınez Garc´ıa SUBATECH, CNRS/IN2P3, Ecole´ des Mines de Nantes, Universit´ede Nantes, 4 rue Alfred Kastler, 44307 Nantes, France (Dated: April 5, 2013) In the last 20 years, heavy-ion collisions have been a unique way to study the hadronic matter in the laboratory. Its phase diagram remains unknown, although many experimental and theoretical studies have been undertaken in the last decades. After the initial experiences accelerating heavy nuclei onto fixed targets at the AGS (BNL, USA) and the SPS (CERN, Switzerland), the Relativistic Heavy Ion Collider (RHIC) at BNL was the first ever built heavy-ion collider. RHIC delivered its first collisions in June 2000 boosting the heavy-ion community. Impressive amount of experimental results has been obtained by the four major experiments at RHIC: PHENIX, STAR, PHOBOS and BRAHMS. In November 2010, the Large Hadron Collider (LHC) at CERN delivered lead-lead collisions at unprecedented center-of- mass energies, 14 times larger than that at RHIC. The three major experiments, ALICE, ATLAS and CMS, have already obtained many intriguing results. Needless to say that the heavy-ion programs at RHIC and LHC promise fascinating and exciting results in the next decade. The first part of the lectures will be devoted to introduce briefly the QCD descrip- tion of the strong interaction (as part of the Standard Model of Particle Physics) and to remind some basic concepts on phase transitions and on the phase diagram of matter. In the second part, I will focus on the properties of matter at energy densities above ≈1 GeV/fm3.
    [Show full text]
  • Deconfinement and Chiral Symmetry Restoration in QCD with Fundamental and Adjoint Fermions
    Corfu Summer Institute on Elementary Particle Physics, 1998 PROCEEDINGS Deconfinement and chiral symmetry restoration in QCD with fundamental and adjoint fermions Frithjof Karsch Fakult¨at f¨ur Physik, Universit¨at Bielefeld, D-33615 Bielefeld, Germany E-mail: [email protected] Abstract: We discuss the critical behaviour of strongly interacting matter close to the QCD phase transition. Emphasis is put on a presentation of results from lattice calculations that illustrate de- confining as well as chiral symmetry restoring features of the phase transition. We show that both transitions coincide in QCD while they fall apart in an SU(3) gauge theory coupled to adjoint fermions. 1. Introduction ment and chiral symmetry breaking for the QCD phase transition. In which respect is the QCD phase transition The interest in analyzing the properties of QCD deconfining and/or chiral symmetry restoring? at non-zero temperature is twofold. On the one In the next section we will address this question hand it is the goal to reach a quantitative de- and will present some basic results on the QCD scription of the behaviour of matter at high tem- equation of state and critical parameters at the perature and density. This does provide impor- transition point obtained from lattice QCD. In tant input for a quantitative description of exper- section 3 we will discuss deconfinement and chiral imental signatures for the occurrence of a phase symmetry restoration in an SU(3) gauge theory transition in heavy ion collisions and should also with adjoint fermions. In section 5 we give our help to understand better the phase transitions conclusions.
    [Show full text]
  • Confinement and Deconfinement in Gauge Theories Kieran Holland
    Confinement and Deconfinement in Gauge Theories by Kieran Holland Submitted to the Department of Physics in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY June 1999 © Massachusetts Institute of Technology 1999. All rights reserved. A uthor ....................................................... .... Department of Physics June 4th, 1999 C ertified by ...................................... Uwe-Jens Wiese Associate Professor Thesis Supervisor Accepted by..........................- . ..... .. Thomas J. Grtak Associate Department Head for Education ASSACHUSETTS INSTITUTE OF TECHNOLOGY L? L18kA kIES Confinement and Deconfinement in Gauge Theories by Kieran Holland Submitted to the Department of Physics on June 4th, 1999, in partial fulfillment of the requirements for the degree of Doctor of Philosophy Abstract In this thesis, we examine properties of the confined and deconfined phases of non- Abelian gauge theories. In one part of the thesis, we examine a String Theory pre- diction made for Supersymmetric Yang-Mills theory. The prediction is that a QCD string emanating from a quark and carrying color flux can end on a domain wall which has no color charge. Using effective field theoretic methods, we explain how the domain wall carries the color flux of the QCD string to spatial infinity. We use this explanation to predict the phase structure of Supersymmetric Yang-Mills theory. We also examine universal critical phenomena associated with these domain walls. In the rest of the thesis, we show analytically how static test quarks can be confined, even in the deconfined bulk phase. We observe this unusual confinement numerically in an effective field theory for the gauge theory using highly efficient cluster techniques.
    [Show full text]