Bulk viscous corrections to screening and damping in the deconfined phase at high temperature

Non-equilibrium corrections in a hot QCD medium modify the "hard thermal loops" (HTL) which determine the resummed propagators for gluons with soft momenta as well as the Debye screening and Landau damping mass scales. We focus on bulk viscous corrections to a thermal fixed point. The screening and damping mass scales are sensitive to the bulk pressure and perhaps to (pseudo-) critical dynamical scaling of the bulk viscosity in the vicinity of a second-order critical point. This would affect the properties of quarkonium bound states in the deconfined phase.Comment: 7 pages; Proceedings of Critical Point and Onset of Deconfinement - CPOD2017; 7--11 August, 2017, Stony Brook University, Stony Brook, NY; to be published in PoS (SISSA

Quarkonium in a non-ideal hot QCD Plasma

Substantial anisotropies should occur in the hot expanding QCD plasma produced in relativistic heavy-ion collisions due to non-vanishing shear viscosity. We discuss the form of the real-time, hard thermal loop resummed propagator for static gluons in the presence of such anisotropies and the consequences for quarkonium binding. It has been predicted that the propagator develops an imaginary part due to Landau damping at high temperature. This generates a much larger width of quarkonium states than the Appelquist-Politzer vacuum estimate corresponding to decay into three gluons. We argue that this might be observable in heavy-ion collisions as a suppression of the Upsilon(1S) --> e+ e- process. Lastly, we consider the heavy quark (singlet) free energy just above the deconfinement temperature. In the "semi-QGP", F(R) at distances beyond 1/T is expected to be suppressed by 1/N as compared to an ideal plasma.Comment: 8 pages, 4 figures; talk given at the Symposium on "High Energy Strong Interactions", aug. 9 -- 13, 2010, Yukawa Institute for Theoretical Physics, Kyoto, Japan; submitted to Prog. Theor. Phys. Supp

Common dimensions for entrepreneurship and strategy: the need for strategic entrepreneurship

Research about the combination between strategy and entrepreneurship is in the early stages. While the benefits of combining entrepreneurship and strategy are well established, specific details and relations between common elements of strategy and entrepreneurship as a concept remain under-developed and unsubstantiated. This paper explores the relation between entrepreneurship and strategy. The common conception is that entrepreneurship has a strong effect on strategy process.entrepreneurship, corporate entrepreneurship, opportunities, uncertainty in business, strategic entrepreneurship.

The Weizs\"acker-Williams distribution of linearly polarized gluons (and its fluctuations) at small x

The conventional and linearly polarized Weizs\"acker-Williams gluon distributions at small x are defined from the two-point function of the gluon field in light-cone gauge. They appear in the cross section for dijet production in deep inelastic scattering at high energy. We determine these functions in the small-x limit from solutions of the JIMWLK evolution equations and show that they exhibit approximate geometric scaling. Also, we discuss the functional distributions of these WW gluon distributions over the JIMWLK ensemble at rapidity $Y\sim 1/\alpha_s$. These are determined by a 2d Liouville action for the logarithm of the covariant gauge function $g^2 \mathrm{tr}\,A^+(q)A^+(-q)$. For transverse momenta on the order of the saturation scale we observe large variations across configurations (evolution trajectories) of the linearly polarized distribution up to several times its average, and even to negative values.Comment: 10 pages, 3 figures; Proceedings of the XLVII International Symposium on Multiparticle Dynamics, Tlaxcala City, Mexico, September 11--15, 2017; to be published in EPJ-Conference

The Transverse Energy as a Barometer of a Saturated Plasma

The evolution of the gluon plasma produced with saturation initial conditions is calculated via Boltzmann transport theory for nuclear collisions at high energy. The saturation scale increases with the nuclear size and the beam energy, and thus we find that the perturbative rescattering rate decreases relative to the initial longitudinal expansion rate of the plasma. The effective longitudinal pressure remains significantly below the lattice QCD pressure until the plasma cools to near the confinement scale. Therefore, the transverse energy per unit of rapidity and its dependence on beam energy provides a sensitive test of gluon saturation models: the fractional transverse energy loss due to final state interactions is smaller and exhibits a weaker energy dependence than if ideal (nondissipative) hydrodynamics applied throughout the evolution.Comment: 4 Pages, LaTex, 2 Figures; Contribution to the 15th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (QM 2001), Long Island, New York, January 15 - 20, 200

Particle production in high-energy collisions beyond the shockwave limit

We compute next to eikonal (NE) and next to next to eikonal (NNE) corrections to the Lipatov vertex due to a finite target thickness. These arise from electric field insertions into the eikonal Wilson lines. We then derive a $k_T$-factorization formula for single inclusive gluon production at NNE accuracy and find that nuclear effects are absent. We also analyze NNE corrections to two-gluon production where some of the contributions are found to exhibit corrections proportional to $A^{2/3}$.Comment: 11 pages, 5 figures, corrected the result for the vertex, added derivation of two-gluon production cross section, published versio