FIAS Scientific Report 2011 - Frankfurt Institute for Advanced Studies ...

More documents

Recommendations

Info

Dynamical equilibration of the strongly-interacting parton matter Collaborators: V. Ozvenchuk 1 , O. Linnyk 4 , M. Gorenstein 1,3 , W. Cassing 4 , E. Bratkovskaya 1,2 1 Frankfurt Institute for Advanced Studies, 2 Institut für Theoretische Physik, Johann Wolfgang Goethe University, Frankfurt am Main, Germany, 3 Bogolyubov Institute for Theoretical Physics, Kiev, Ukraine, 4 Institut für Theoretische Physik, Universität Giessen We study kinetic and chemical equilibration in ’infinite’ parton-hadron matter within the Parton-Hadron-String Dynamics (PHSD) transport approach, which is based on generalized transport equations on the basis of the offshell Kadanoff-Baym equations for Green’s functions in phase-space representation. The basis of the partonic phase description is the dynamical quasiparticle model (DQPM) matched to reproduce lattice QCD results – including the partonic equation of state – in thermodynamic equilibrium. The transition from partonic to hadronic degrees of freedom is described by covariant transition rates for fusion of quark-antiquark pairs or three quarks (antiquarks), obeying flavor current conservation, color neutrality as well as energy-momentum conservation. The ’infinite’ matter is simulated within a cubic box with periodic boundary conditions initialized at various values for baryon density (or chemical potential) and energy density. The size of box is fixed to 9 3 fm 3 . We start with light (u,d) and strange quarks, antiquarks and gluons with random space positions and the momenta distributed exponentially, but not with equilibrium distribution. A sign for chemical equilibration is the stabilization of the numbers of partons of the different species in time for t → ∞. In Fig. 1(a) we show the particle abundances of the u,d,s quarks+antiquarks and gluons as functions of time for system initialized at energy density of 1.1 GeV/fm3 . �� (a) (b) (a) Abundances of the u (solid red), d (short-dashed black), s (dash-dotted blue) quarks+antiquarks and gluons (dashed green) as a function of time for system initialized at energy density of 1.1 GeV/fm3 . (b) The spectrum of u quarks (antiquarks) for system initialized at energy density of 4.72 GeV/fm3 from the PHSD simulations (solid red) in comparison to the DQPM model (dashed blue). Choosing the momenta of the partons in the narrow interval |p| ∈ [p−, p+], we construct the distribution of partons with given energy and momentum as � � �� dN g(q, ¯q) dωd p = V d g(q, ¯q) 2π 3 |pmid| 2 ωρ g(q, ¯q)(ω, pmid)n B(F)(ω/T), (1) where pmid = (p+ − p−)/2. In Fig. 1(b) we show d 2 N/dωd p for u quarks obtained by the PHSD simulations of infinite partonic system as initialized at energy density of 4.72 GeV/fm 3 . For comparison, we present on the same plot the DQPM assumption for the respective distribution. We find a good agreement between the DQPM distribution and the result of the microscopic simulations. Related publication in 2011: V. Ozvenchuk, E. Bratkovskaya, O. Linnyk, M. Gorenstein, W. Cassing, arXiv:1101.0218v1 [nucl-th]. 46 �
Dileptons from the strongly interacting quark-gluon plasma (sQGP) Collaborators: O. Linnyk 1,3 , E. L. Bratkovskaya 1,2 , V. Ozvenchuk 2 , J. Manninen 1,3 , W. Cassing 3 , C.M. Ko 4 1 Institut für Theoretische Physik, Goethe Universität Frankfurt am Main, Germany, 2 Frankfurt Institute for Advanced Studies, Germany, 3 Institut für Theoretische Physik, Justus Liebig Universität Gießen, Germany 4 Cyclotron Institute and Department of Physics and Astronomy, Texas A&M University, College Station, Texas, USA We address dilepton production in Au+Au collisions at √ sNN = 200 GeV by employing the parton-hadronstring dynamics (PHSD) off-shell transport approach [3,4,6]. Within the PHSD one solves generalized transport equations and consistently describes the full evolution of a relativistic heavy-ion collision [2]. We calculated the dilepton radiation from partonic interactions through the reactions q ¯q → γ∗ , q ¯q → γ∗ + g and qg → γ∗q ( ¯qg → γ∗ ¯q) in the early stage of relativistic heavy-ion collisions with the differential cross sections for electromagnetic radiation calculated with the same propagators as those incorporated in the PHSD transport approach [1]. By comparing our calculated results [3,4] to the data, we have studied the relative importance of different dilepton production mechanisms and addressed in particular the ’PHENIX puzzle’ of a large enhancement of dileptons in the mass range from 0.15 to 0.6 GeV as compared to the emission of hadronic states. Similar to our findings at SPS energies [5], we find that the partonic dilepton production channels are visible in the intermediate-mass region between the φ and J/Ψ peaks [3,4,6,9]. Our studies have demonstrated that the observed excess in the low mass dilepton regime cannot be attributed to partonic productions as expected earlier. Thus the ’PHENIX puzzle’ still has no explanation from the theoretical approaches so far. The solution has to be relegated to the experimental side. In fact, the STAR collaboration has taken independent dilepton data for centralities different from the PHENIX measurements and also with different detector acceptances. Our calculations allow to match with the different experimental conditions and thus to provide a ’theoretical link’ between the different measurements. To this extent, we have provided our predictions for the conditions of the STAR experiment, which happen to be in a rough agreement with the preliminary data [4]. �� Figure 1: The PHSD results for the mass differential dilepton spectra in case of inclusive Au+Au collisions at √ s = 200 GeV in comparison to the data from PHENIX (left pannel) and STAR (right pannel) Collaborations. Related publications in 2011: 1) O. Linnyk, J. Phys. G38 (2011) 025105. 2) E.L. Bratkovskaya, W. Cassing, V.P. Konchakovski, O. Linnyk, Nucl. Phys. A856 (2011) 162. 3) O. Linnyk, W. Cassing, E.L. Bratkovskaya, J. Manninen, Nucl. Phys. A855 (2011) 273. 4) O. Linnyk, W. Cassing, J. Manninen, E.L. Bratkovskaya, C.M. Ko, arXiv:1111.2975, Phys. Rev. C (in print). 5) O. Linnyk, E.L. Bratkovskaya, V. Ozvenchuk, W. Cassing, C.M. Ko, Phys. Rev. C84 (2011) 054917. 6) J. Manninen, E.L. Bratkovskaya, W. Cassing, O. Linnyk, Eur. Phys. J. C71 (2011) 1615. 7) O. Linnyk, E.L. Bratkovskaya, W. Cassing, J. Phys. Conf. Ser. 316 (2011) 012028. 8) O. Linnyk, E.L. Bratkovskaya, J. Manninen, W. Cassing, J. Phys. Conf. Ser. 312 (2011) 012010. 9) J. Manninen, E.L. Bratkovskaya, W. Cassing, O.Linnyk, J. Phys. Conf. Ser. 270 (2011) 012039. 10) O. Linnyk, E.L. Bratkovskaya, W. Cassing, PoS BORMIO2011 (2011) 029. 47
Page 1 and 2: FIAS Scientific Report 2011
Page 3: FIAS Scientific Report 2011 Table o
Page 6 and 7: Physics Research highlights 2011 To
Page 9 and 10: 1. Partner Research Centers 9
Page 11 and 12: ExtreMe Matter Institute EMMI by Ca
Page 13 and 14: Bernstein Focus Neurotechnology Fra
Page 15 and 16: 2. Graduate Schools 15
Page 17 and 18: participants reported on their proj
Page 19 and 20: Courses offered at FIGSS Summer Sem
Page 21 and 22: 3. FIAS Scientific Life 21
Page 23 and 24: 28.07.2011 Prof. Dr. Victor Flambau
Page 25 and 26: Conferences and meetings (co)organi
Page 27 and 28: 4. Research Reports 4.1 Nuclear Phy
Page 29 and 30: Hydrodynamics of a quark droplet Co
Page 31 and 32: Production of hyper-nuclei in react
Page 33 and 34: On production and properties of mul
Page 35 and 36: Monte Carlo modeling microdosimetry
Page 37 and 38: Monte Carlo simulation of the spall
Page 39 and 40: Dimuon radiation within a (3+1)d hy
Page 41 and 42: Initial state anisotropies and thei
Page 43 and 44: Chiral hadronic model including res
Page 45: Trace anomaly and the vector coupli
Page 49 and 50: Space-time evolution of the magneti
Page 51 and 52: Extreme isospin in heavy nuclei Col
Page 53 and 54: Production of heavy and superheavy
Page 55 and 56: The phase diagram in T -µB-Nc spac
Page 57 and 58: Critical Zeeman Fields for Unitary
Page 59 and 60: BCS-BEC Crossover in 2D Fermi Gases
Page 61 and 62: Applications of a chiral SU(3) mode
Page 63 and 64: The phase diagram of black holes in
Page 65 and 66: Black holes in short scale modified
Page 67 and 68: Fractal dimensions and micro-struct
Page 69 and 70: Untangling the interactions between
Page 71 and 72: Stimulus information coded by spike
Page 73 and 74: Non-stationarity of neuronal activi
Page 75 and 76: Timescale of information processing
Page 77 and 78: Discovery of agency in 6 and 8-mont
Page 79 and 80: Power spectra of the natural input
Page 81 and 82: Self-organization in recurrent neur
Page 83 and 84: Learning mechanisms underlying visu
Page 85 and 86: Emerging Bayesian priors in a self-
Page 87 and 88: Non-linear generative models and th
Page 89 and 90: Preference elicitation and Bayesian
Page 91 and 92: 4.3 Biology, Chemistry, Molecules,
Page 93 and 94: DNA unzipping Collaborators: S.N. V
Page 95 and 96: Statistical mechanics of protein fo
Page 97 and 98:
Phase transitions in large clusters
Page 99 and 100:
Photo-processes in fullerenes and e
Page 101 and 102:
Assessment of complex DNA damage Co
Page 103 and 104:
Novel light sources: Crystalline un
Page 105 and 106:
Monte-Carlo code for channeling dyn
Page 107 and 108:
Programs for many-body descriptions
Page 109 and 110:
Are 12 C radiation effects in liver
Page 111 and 112:
Objective identification of residue
Page 113 and 114:
Structural basis for the dual RNA-r
Page 115 and 116:
The ALICE High Level Trigger Collab
Page 117 and 118:
Arithmetic over Galois fields on mo
Page 119 and 120:
High Performance GPU-based DGEMM an
Page 121 and 122:
How stable are transport model resu
Page 123 and 124:
5. Talks and Publications 123
Page 125 and 126:
Conference and Seminar Talks 2011
Page 127 and 128:
Page 129 and 130:
Conference and Seminar Talks 2011 W
Page 131 and 132:
Page 133 and 134:
FIAS conference abstracts and poste
Page 135 and 136:
FIAS conference abstracts and poste
Page 137 and 138:
FIAS Publications 2011 - Journal pu
Page 139 and 140:
Page 141 and 142:
Page 143 and 144:
Page 145 and 146:
Page 147 and 148:
FIAS publications 2011 - Conference
Page 149 and 150:
Page 151 and 152:
Page 153 and 154:
Page 155 and 156:
Page 157 and 158:
Page 159 and 160:
FIAS publications 2011 - Patents 24
Page 161:
The success of FIAS would not have
show all

FIAS Scientific Report 2011 - Frankfurt Institute for Advanced Studies ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?