A Novel Heavy Quark Suppression Mechanism in the QGP Time evolution Presentation Title Slide Notes “UNCLASSIFIED” marking of slides is not a security requirement and may be deleted from the Slide Master (View › Master › Slide Master). In general, slides should be marked “UNCLASSIFIED” if there is potential for confusion or misinterpretation of something that could be deemed classified. For guidance on marking slides containing classified and unclassified controlled information, see the Protecting Information Web site at http://int.lanl.gov/security/protectinfo/. Ivan Vitev, Nuclear Theory, T-16 , LANL "Characterization of the Quark-Gluon Plasma with Heavy Quarks” Seminar June 25 - 28, 2008, Bad Honnef, Germany

Outline of the Talk Jet tomography of the QGP Success of jet quenching for light hadrons, QGP tomography The heavy quark puzzle at RHIC. A space-time picture of hadronization Collisional dissociation of hadrons in dense QCD matter Dissociation: new approach to D- and B-mesons suppression in the QGP Light cone wave-functions. Mesons propagation in matter Phenomenological results for RHIC and the LHC Heavy resonances and partial chiral symmetry restoration Hadrons and  symmetry. Formation time of resonances in the medium Interaction and decay of heavy resonances in matter Experimental detection techniques Summary and outlook Universal modification of fragmentation functions in the QGP Talk based upon: A.Adil, I.Vitev, Phys. Lett. B649 (2007) Ch.Markert, R.Bellwied, I.Vitev, Phys. Lett. B to be submitted R. Sharma, I.Vitev, in progress

Light Hadron Quenching Nuclear modification factor Predictions of this formalism tested vs particle momentum, C.M. energy, centrality I.V., Phys.Lett.B 639 (2006) Constrained by the gluon rapidity (entropy) density

Non-Photonic Electron / Heavy Flavor Quenching Proceed the same way to heavy flavor in A+A collisions Single electron measurements (presumably from heavy quarks) may be problematic M.Djordjevic, M.Gyulassy, Nucl.Phys.A (2004) Radiative Energy Loss using (D)GLV (both c + b) Radiative + Collisional + Geometry (both c + b) (overestimated) Deviation by a factor of two Is it accidental or is it symptomatic? S. Wicks et al., Nucl.Phys.A (2007)

The Space-Time Picture of Hadronization In mesoscopic systems one has to account for the space-time evolution Inside-outside cascade J.D. Bjorken, Lect.NotesPhys.56, (1987) Correctly accounts for the leading energy and mass dependence. Lack of control over t0 Outside-inside cascade A. Bialas, M.Gyulassy, Nucl.Phys.B 291, (1987) Correctly points at the reduction of tform at large values of x. Specific for Lund string fragmentation. Mass dependence obscured

Evaluating the Formation Times Problem: treated in the same way as light quarks + B D QGP extent (~5 fm) Parton Hadron 20 fm 1.5 fm 0.4 fm Fragmentation and dissociation of hadrons from heavy quarks inside the QGP

Collisional Dissociation of D / B Mesons Conceptually different approach to heavy flavor suppression Time evolution A. Adil, I. Vitev, Phys. Lett. B649, 139 (2007), hep-ph/0611109

Light Cone Wave Functions From general theory of LCWF for the lowest-lying Fock state - Transverse momentum scale - Longitudinal momentum fractions S.Brodsky, D.S.Hwang, B.Q.Ma, I.Schmidt, Nucl.Phys.B 592 (2001) Results for heavy flavor Expansion in Fock components LO Fock component Mean Peaked at large x Models such as coalescence should use plausible wave functions, especially for heavy flavor

Medium-Modified Heavy Meson Initial distribution: Resum using GLV the multiple scattering in impact parameter (B,b) space Heavy meson acoplanarity: ? Broadening (separation) the q q-bar pair:

Initial Conditions (Hard Parton Spectra) Simultaneous fragmentation and dissociation call for solving a system of coupled equations I.V.,T.Goldman,M.Johnson,J.W.Qiu, Phys.Rev.D74 (2006) Example: radioactive decay chain Initial conditions Proposed back-2-back D / B triggered correlations

Heavy Meson Dissociation at RHIC and LHC Coupled rate equations The asymptotic solution in the QGP - sensitive to t0~0.6 fm and expansion dynamics Features of energy loss B-mesons as suppressed as D-mesons at pT~ 15-20 GeV at the LHC Unique feature A. Adil, I. Vitev, Phys. Lett. B649, 139 (2007)

Quenching of Non-Photonic Electrons Full semi-leptonic decays of C- and B- mesons and baryons included. PDG branching fractions and kinematics. PYTHIA event generator Similar to light , however, different physics mechanism B-mesons are included. They give a major contribution to (e++e-) Note on applicability D-, B-mesons to (e++e-) to 25 GeV

Areas of Improvement Incorporate radiative and collisional energy loss at really high pT Main criticism: what are the modifications to a fragmentation process, modified fragmentation functions, coalscence, … ( We wanted to solve this, the hierarchy problem, GUT, the baryon asymmetry, dark matter … but we couldn’t in the same paper ) A+A These are not “modified fragmentation functions” A. Majumder, X.N.Wang (2008)

R. Sharma, I. Vitev, in prepration A Possible Path Definition of the fragmentation functions The apparent duality between parton distribution functions and fragmentation functions is understandable From D(z) parameterizations or LCWF extract information about matrix elements We may gain insight of universal (T) modifications to fragmentation functions R. Sharma, I. Vitev, in prepration

Effects of Partial Chiral Symmetry Restoration Kaon Lagrangian Scale of chiral symmetry restoration - Includes approximately strange quarks Mass shifts G. Brown, M.Rho, Rev. Mod. Phys., (2001) Width broadening Phi meson L. Holt, K.Haglin, J. Phys. G31, S245 (2005) Manifestation for baryons L. Glozman, Phys.Lett. B475, 329 (2000) Evidence for possible chiral symmetry restoration Important to include baryons (,*) in experimental searches at finite T

Motivation / Estimates - a Simple Case Mass of heavy resonances: falls in the right region to ensure early formation Quick evaluation ( z = 0.7 ) QGP formation (in the absence of dynamical calculation) Cross sections and z distributions

Formation Time of Resonances Distributions One has to approximate fragmentation functions. Normalizations cancel in the ratio RHIC LHC

In-medium Lifetime (Stronger Constraints) Spectral function: medium broadening Remember the dilation factor Reduction if the lifetime is critical if any effects are to be observed in the resonance channel (upper pT limit) URQMD study: any signal in pT 0-2 GeV strongly affected by hadronic rescattering of decay products (lower pT limit) L. Holt, K.Haglin, J. Phys. G31, S245 (2005) Phi meson M.Bleicher et al., Phys. Lett. B530, 81 (2002)

Triggered Measurements Ensure maximum medium size without changing the formation times pT associated pT trigger There is always a time distribution Many of the resonances will be dissociated. We are concerned with those that survive .

Summary of Open Heavy Flavor Suppression Collisional QGP-induced B- / D-meson dissociation Derived formation and dissociation times in the QGP. They are short Solved the set of coupled rate equations. More sensitive to QGP properties and formation / expansion dynamics than e-loss Found that suppression of non-photonic electrons from heavy mesons, including B, is large. Not inconsistent with light pions B-mesons are as suppressed as D-mesons at pT ~ 10 GeV, unique Toward experimental resolution of the B- / D- puzzle Identify the B- and D-meson contribution to the inclusive electron spectra and the suppression factor RAA separately for Bs and Ds This will certainly motivate us to improve the calculation: modified fragmentation functions (really) and folding in energy loss. Searches for chiral symmetry restoration Identified the phase space and channels if those searches are to be done experimentally wit heavy resonances.

Outline of the Talk Jet tomography of the QGP Success of jet quenching for light hadrons, QGP tomography The heavy quark puzzle at RHIC. A space-time picture of hadronization Collisional dissociation of hadrons in dense QCD matter Dissociation: new approach to D- and B-mesons suppression in the QGP Light cone wave-functions. Mesons propagation in matter Phenomenological results for RHIC and the LHC Heavy resonances and partial chiral symmetry restoration Hadrons and  symmetry. Formation time of resonances in the medium Interaction and decay of heavy resonances in matter Experimental detection techniques Summary and outlook Universal modification of fragmentation functions in the QGP Talk based upon: A.Adil, I.Vitev, Phys. Lett. B649 (2007) Ch.Markert, R.Bellwied, I.Vitev, Phys. Lett. B to be submitted R. Sharma, I.Vitev, in progress

I.V., M.Gyulassy, Phys.Rev.Lett. 89 (2002) Jet Tomography Determining the properties of the QGP: SPS RHIC LHC I.V., M.Gyulassy, Phys.Rev.Lett. 89 (2002) F.Karsch, Nucl.Phys.A698 (2002)

Single inclusive pion suppression at the LHC Running Fixed High pT suppression at the LHC can be comparable and smaller than at RHIC LHC quenching follows the steepness of the partonic spectra Reduced sensitivity to medium properties S.Wicks et al., in progress

Direct photon at the LHC Direct photons also have limited sensitivity: isospin effects, cold nuclear matter e-loss Prompt photons + Fragmentation photons Better jet interaction measures? Direct photon tagging: can be compromised by fragmentation photons

Non-Photonic Electron / Heavy Flavor Quenching Radiative and collisional energy loss Langevin simulation of heavy quark diffusion S. Wicks et al., (2005) N. Armesto et al., (2006) Ratio: Opacity of the QGP H. van Hees, R. Rapp, (2005) G. Moore, D.Teaney (2005) Diffusion coefficient D and eventually Existence of heavy heavy resonances near Tc in the QGP

The Path Forward An interesting idea valid physics explanation To understand heavy flavor modification in the QGP we need direct and separate measurements of D- and B-mesons, excellent statistics Measurable at RHIC Measurable at the LHC A.Adil, I.Vitev, Phys. Lett. B (2006) W.Horowitz, M. Gyulassy, (2007) Meson dissociation PQCD, Transport String theory AdS/CFT 10-15 50-100 Never PT [GeV]

Heavy Flavor Elliptic Flow and Suppression Test coalescence model fits to the v2 of light hadrons via heavy flavor Understand the structure of mesons light cone wave functionsc Sensitive to the opacity of the QGP and its formation time D. Molnar (2004) A. Adil, I. Vitev, Phys.Lett.B (2007)

Heavy Quark Production and Correlations Fast convergence of the perturbative series Possibility for novel studies of heavy quark-triggered (D and B) jets: hadron composition of associated yields

Scales in Thermalized QGP (GP) Experimental: Bjorken expansion Theoretical: Gluon dominated plasma Energy density Transport coefficients (not a good measure for expanding medium) Define the average for Bjorken

Langevin Simulation of Heavy Quark Diffusion Input in a Langevin simulation of heavy quark diffusion H. van Hees, I.V., R. Rapp, in preparation Drag coefficient: Diffusion coefficient: Equilibration is imposed by Einstein’s fluctuation-dissipation relation: Radiative energy loss is dominant except for b-quarks and very small systems

Transport + Quenching Approach Numerical results for heavy quark diffusion Results are preliminary H. van Hees, I.V., R. Rapp, in preparation The suppression and v2 are large when e-loss and q-resonance interactions are combined Normal hierarchy: c quarks are significantly more suppressed than b-quarks

Hard Probes from Factorized PQCD xbP’ P xaP Pd Single and double inclusive hard production in PQCD - applicable from photons to heavy quarks X Pd / zd Pc / zc Single and double inclusive hard production in PQCD - applicable from photons to heavy quarks X Pc Power laws: Quenching factor

Jet cross sections: comparison to LO and NLO PQCD I.V., S. Wicks, in preparation Good comparison to the shape at LO. Meaningful K-factor Even better comparison at NLO.

Jets from Factorized PQCD Single and double inclusive hard production in PQCD - applicable from photons to heavy quarks P’ xbP’ P xaP Pd X Pd / zd Pc / zc X Pc For jets: Caveat: parton-hadron duality Jet cross sections are more inclusive and therefore more robust PQCD observables CDF studies: J.Collins, D.Soper, G.Sterman, Nucl.Phys.B (1983)