Hydrodynamic Flow and Jet Induced Mach Shocks at RHIC and LHC

We discuss the present collective flow signals for the phase transition to quark-gluon plasma (QGP) and the collective flow as a barometer for the equation of state (EoS). A study of Mach shocks induced by fast partonic jets propagating through the QGP is given. We predict a significant deformation of Mach shocks in central Au+Au collisions at RHIC and LHC energies as compared to the case of jet propagation in a static medium. Results of a hydrodynamical study of jet energy loss are presented.Comment: 15 pages, 8 figure

Conserved Charge Fluctuations in a Chiral Hadronic Model including Hadrons and Quarks

In this work the susceptibility coefficients of the strange and non-strange quark number of second and fourth order are presented. The results at zero baryonchemical potential are obtained using a well tested chiral effective model including all known hadron degrees of freedom and additionally incorporating quarks and gluons in a PNJL model approach. Quark number susceptibilities are sensitive to the fundamental degrees of freedom in the model and signal the shift from massive hadrons to light quarks at the deconfinement transition by a sharp rise at the critical temperature. Furthermore, all susceptibilities are found to be largely suppressed by repulsive vector field interactions of the particles. In the hadronic sector vector repulsion of baryon resonances restrains fluctuations to a region determined in lattice QCD. However, in the quark sector above $T_c$ even small vector field interactions of quarks quench all fluctuations almost completely. For this reason, vector field interactions for quarks have to vanish in the deconfinement limit.Comment: 8 pages, 4 figure

QCD Equation of State From a Chiral Hadronic Model Including Quark Degrees of Freedom

This work presents an effective model for strongly interacting matter and the QCD equation of state (EoS). The model includes both hadron and quark degrees of freedom and takes into account the transition of chiral symmetry restoration as well as the deconfinement phase transition. At low temperatures $T$ and baryonic densities $\rho_B$ a hadron resonance gas is described using a SU(3)-flavor sigma-omega model and a quark phase is introduced in analogy to PNJL models for higher $T$ and $\rho_B$. In this way, the correct asymptotic degrees of freedom are used in a wide range of $T$ and $\rho_B$. Here, results of this model concerning the chiral and deconfinement phase transitions and thermodynamic model properties are presented. Large hadron resonance multiplicities in the transition region emphasize the importance of heavy-mass resonance states in this region and their impact on the chiral transition behavior. The resulting phase diagram of QCD matter at small chemical potentials is in line with latest lattice QCD and thermal model results.Comment: 5 pages 3 figures; presented at the 8th International Workshop on "Critical Point and Onset of Deconfinement - CPOD 2013" Napa, March 11-15, 201

Social, behavioral, and cognitive influences on upper echelons during strategy process

This study reviews research on the social, behavioral, and cognitive influences on CEOs, top management teams (TMTs), and the CEO-TMT interface during strategic decision making. We identify the key issues examined in this research over the past 10 years and relate developments in the field to previous knowledge in this area. We also attempt to identify what constitutes an established body of knowledge in the field and, therefore, areas that need additional examination. Our review indicates that while there has been an explosion of research on the influence of CEO personality and TMT social processes on strategy process, much remains to be done in terms of examining CEO and TMT cognition, particularly at the level of the CEO-TMT interface

A better way of managing major risks

The article focuses on important distinction between enterprise risk management and strategic risk management and regarding the role of board directors in the risk management. It mentions that different way to identify and manage risk such as financial crisis to inadequate risk management by banks and other financial institutions, risks with subprime mortgages and increasing the risk for profit.

Missing the point of the practice-based view

In this article, we address Jarzabkowski et al.’s strategy-as-practice criticism of Bromiley and Rau’s practice-based view as ignoring the “who” and “how” of practice implementation. Bromiley and Rau explicitly note that any statistical model under the practice-based view should consider mediating and moderating variables that depend on the specific practice and context but that the article would not attempt to identify such variables. Strategy-as-practice’s focus on the “who” and “how” of a practice are two of many such potential mediating or moderating variables. More fundamentally, strategy-as-practice scholars’ discomfort with the practice-based view may arise both from their different definitions of practice and their different approaches to strategy research. Without diminishing the strategy-as-practice’s contribution to strategy research, we argue for the additional value in the practice-based view’s call for systematic, large-scale, quantitative studies that establish the performance impact of specific practices across populations of organizations

Mach Cones and Hydrodynamic Flow: Probing Big Bang Matter in the Laboratory

A critical discussion of the present signals for the phase transition to quark-gluon plasma (QGP) is given. Since hadronic rescattering models predict much larger flow than observed from 1 to 50 A GeV laboratory bombarding energies, this observation is interpreted as potential evidence for a first-order phase transition at high baryon density. A detailed discussion of the collective flow as a barometer for the equation of state (EoS) of hot dense matter at RHIC follows. Here, hadronic rescattering models can explain < 30 % of the observed elliptic flow v_2 for $p_T > 2$ GeV/c. This is interpreted as an evidence for the production of superdense matter at RHIC. The connection of v_2 to jet suppression is examined. A study of Mach shocks generated by fast partonic jets propagating through the QGP is given. The main goal is to take into account different types of collective motion during the formation and evolution of this matter. A significant deformation of Mach shocks in central Au+Au collisions at RHIC and LHC energies as compared to the case of jet propagation in a static medium is predicted. A new hydrodynamical study of jet energy loss is presented.Comment: 18 pages, 12 figures, presented at the IWCF 2006, Nov. 21-24, Hangzhou, Chin

Baryon Resonances in a Chiral Hadronic Model for the QCD Equation of State

In this paper we study the influence of hadronic resonances on the phase diagram calculated with an effective chiral flavour SU(3) model. We show that varying the couplings of the baryonic resonances to the attractive scalar and the repulsive vector fields has a major impact on the order and location of the chiral phase transition and the possible existence of a critical end point as well as on the thermodynamic properties of the model. Furthermore, we study (strange) quark number fluctuations and show the related susceptibilities both at zero baryochemical potential and when crossing the phase transition line at three different points in the T-mu plane. We obtain the best agreement with current lattice data if we choose a rather strong vector coupling which in our model limits the phase transition to a smooth crossover and implies the non-existence of a critical end point.Comment: 10 pages, 9 figure